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Showing 1-20 of about 182 results.
Extended X-Ray Emission around FR II Radio Galaxies: Hot Spots, Lobes, and Galaxy ClustersJimenez-Gallardo, A.Massaro, F.Paggi, A.D'Abrusco, RaffaelePrieto, M. A.Peña-Herazo, H. A.Berta, V.Ricci, F.Stuardi, C.Wilkes, Belinda J.O'Dea, C. P.Baum, S. A.Kraft, Ralph P.Forman, William R.Jones-Forman, ChristineMingo, B.Liuzzo, E.Balmaverde, B.Capetti, A.Missaglia, V.Hardcastle, M. J.Baldi, R. D.Morabito, L. K.DOI: info:10.3847/1538-4365/abcecdv. 25231
Jimenez-Gallardo, A., Massaro, F., Paggi, A., D'Abrusco, Raffaele, Prieto, M. A., Peña-Herazo, H. A., Berta, V., Ricci, F., Stuardi, C., Wilkes, Belinda J., O'Dea, C. P., Baum, S. A., Kraft, Ralph P., Forman, William R., Jones-Forman, Christine, Mingo, B., Liuzzo, E., Balmaverde, B., Capetti, A., Missaglia, V., Hardcastle, M. J., Baldi, R. D., and Morabito, L. K. 2021. "Extended X-Ray Emission around FR II Radio Galaxies: Hot Spots, Lobes, and Galaxy Clusters." The Astrophysical Journal Supplement Series 252:31.
ID: 159641
Type: article
Authors: Jimenez-Gallardo, A.; Massaro, F.; Paggi, A.; D'Abrusco, Raffaele; Prieto, M. A.; Peña-Herazo, H. A.; Berta, V.; Ricci, F.; Stuardi, C.; Wilkes, Belinda J.; O'Dea, C. P.; Baum, S. A.; Kraft, Ralph P.; Forman, William R.; Jones-Forman, Christine; Mingo, B.; Liuzzo, E.; Balmaverde, B.; Capetti, A.; Missaglia, V.; Hardcastle, M. J.; Baldi, R. D.; Morabito, L. K.
Abstract: We present a systematic analysis of the extended X-ray emission discovered around 35 FR II radio galaxies from the revised Third Cambridge Catalog (3CR) Chandra Snapshot Survey with redshifts between 0.05 and 0.9. We aimed to (i) test for the presence of extended X-ray emission around FR II radio galaxies, (ii) investigate whether the extended emission origin is due to inverse Compton (IC) scattering of seed photons arising from the cosmic microwave background (CMB) or thermal emission from an intracluster medium (ICM), and (iii) test the impact of this extended emission on hot-spot detection. We investigated the nature of the extended X-ray emission by studying its morphology and compared our results with low-frequency radio observations (i.e., ∼150 MHz) in the TGSS and LOFAR archives, as well as with optical images from Pan-STARRS. In addition, we optimized a search for X-ray counterparts of hot spots in 3CR FR II radio galaxies. We found statistically significant extended emission (>3σ confidence level) along the radio axis of ∼90% and in the perpendicular direction of ∼60% of the galaxies in our sample. We confirmed the detection of seven hot spots in the 0.5-3 keV energy range. In the cases where the emission in the direction perpendicular to the radio axis is comparable to that along the radio axis, we suggest that the underlying radiative process is thermal emission from the ICM. Otherwise, the dominant radiative process is likely nonthermal IC/CMB emission from lobes. We found that nonthermal IC/CMB is the dominant process in ∼70% of the sources in our sample, while thermal emission from the ICM dominates in ∼15% of them.
Physical insights from the spectrum of the radio halo in MACS J0717.5+3745Rajpurohit, K.Brunetti, G.Bonafede, A.van Weeren, R. J.Botteon, A.Vazza, F.Hoeft, M.Riseley, C. J.Bonnassieux, E.Brienza, M.Forman, W. R.Röttgering, H. J. A.Rajpurohit, A. S.Locatelli, N.Shimwell, T. W.Cassano, R.Di Gennaro, G.Brüggen, M.Wittor, D.Drabent, A.Ignesti, A.DOI: info:10.1051/0004-6361/202039591v. 646A135
Rajpurohit, K., Brunetti, G., Bonafede, A., van Weeren, R. J., Botteon, A., Vazza, F., Hoeft, M., Riseley, C. J., Bonnassieux, E., Brienza, M., Forman, W. R., Röttgering, H. J. A., Rajpurohit, A. S., Locatelli, N., Shimwell, T. W., Cassano, R., Di Gennaro, G., Brüggen, M., Wittor, D., Drabent, A., and Ignesti, A. 2021. "Physical insights from the spectrum of the radio halo in MACS J0717.5+3745." Astronomy and Astrophysics 646:A135.
ID: 159562
Type: article
Authors: Rajpurohit, K.; Brunetti, G.; Bonafede, A.; van Weeren, R. J.; Botteon, A.; Vazza, F.; Hoeft, M.; Riseley, C. J.; Bonnassieux, E.; Brienza, M.; Forman, W. R.; Röttgering, H. J. A.; Rajpurohit, A. S.; Locatelli, N.; Shimwell, T. W.; Cassano, R.; Di Gennaro, G.; Brüggen, M.; Wittor, D.; Drabent, A.; Ignesti, A.
Abstract: We present new LOw-Frequency ARray observations of the massive merging galaxy cluster MACS J0717.5+3745, located at a redshift of 0.5458. The cluster hosts the most powerful radio halo known to date. These new observations, in combination with published uGMRT (300-850 MHz) and VLA (1-6.5 GHz) data, reveal that the halo is more extended than previously thought, with a largest linear size of ∼2.2 Mpc, making it one of the largest known halos. The halo shows a steep spectrum (α144 MHz1.5 GHz ∼ -1.4) and a steepening (α1.5 GHz5.5 GHz ∼ -1.9) above 1.5 GHz. We find a strong scattering in spectral index maps on scales of 50-100 kpc. We suggest that such a strong scattering may be a consequence of the regime where inverse Compton dominates the energy losses of electrons. The spectral index becomes steeper and shows an increased curvature in the outermost regions of the halo. We combined the radio data with Chandra observations to investigate the connection between the thermal and nonthermal components of the intracluster medium (ICM). Despite a significant substructure in the halo emission, the radio brightness correlates strongly with the X-ray brightness at all observed frequencies. The radio-versus-X-ray brightness correlation slope steepens at a higher radio frequency (from b144 MHz = 0.67 ± 0.05 to b3.0 GHz = 0.98 ± 0.09) and the spectral index shows a significant anticorrelation with the X-ray brightness. Both pieces of evidence further support a spectral steepening in the external regions. The compelling evidence for a steep spectral index, the existence of a spectral break above 1.5 GHz, and the dependence of radio and X-ray surface brightness correlation on frequency are interpreted in the context of turbulent reacceleration models. Under this scenario, our results allowed us to constrain that the turbulent kinetic pressure of the ICM is up to 10%.
Understanding the radio relic emission in the galaxy cluster MACS J0717.5+3745: Spectral analysisRajpurohit, K.Wittor, D.van Weeren, R. J.Vazza, F.Hoeft, M.Rudnick, L.Locatelli, N.Eilek, J.Forman, W. R.Bonafede, A.Bonnassieux, E.Riseley, C. J.Brienza, M.Brunetti, G.Brüggen, M.Loi, F.Rajpurohit, A. S.Röttgering, H. J. A.Botteon, A.Clarke, T. E.Drabent, A.Domínguez-Fernández, P.Di Gennaro, G.Gastaldello, F.DOI: info:10.1051/0004-6361/202039428v. 646A56
Rajpurohit, K., Wittor, D., van Weeren, R. J., Vazza, F., Hoeft, M., Rudnick, L., Locatelli, N., Eilek, J., Forman, W. R., Bonafede, A., Bonnassieux, E., Riseley, C. J., Brienza, M., Brunetti, G., Brüggen, M., Loi, F., Rajpurohit, A. S., Röttgering, H. J. A., Botteon, A., Clarke, T. E., Drabent, A., Domínguez-Fernández, P., Di Gennaro, G., and Gastaldello, F. 2021. "Understanding the radio relic emission in the galaxy cluster MACS J0717.5+3745: Spectral analysis." Astronomy and Astrophysics 646:A56.
ID: 159559
Type: article
Authors: Rajpurohit, K.; Wittor, D.; van Weeren, R. J.; Vazza, F.; Hoeft, M.; Rudnick, L.; Locatelli, N.; Eilek, J.; Forman, W. R.; Bonafede, A.; Bonnassieux, E.; Riseley, C. J.; Brienza, M.; Brunetti, G.; Brüggen, M.; Loi, F.; Rajpurohit, A. S.; Röttgering, H. J. A.; Botteon, A.; Clarke, T. E.; Drabent, A.; Domínguez-Fernández, P.; Di Gennaro, G.; Gastaldello, F.
Abstract: Radio relics are diffuse, extended synchrotron sources that originate from shock fronts generated during cluster mergers. The massive merging galaxy cluster MACS J0717.5+3745 hosts one of the more complex relics known to date. We present upgraded Giant Metrewave Radio Telescope band 3 (300-500 MHz) and band 4 (550-850 MHz) observations. These new observations, combined with published VLA and the new LOFAR HBA data, allow us to carry out a detailed, high spatial resolution spectral analysis of the relic over a broad range of frequencies. The integrated spectrum of the relic closely follows a power law between 144 MHz and 5.5 GHz with a mean spectral slope α = -1.16 ± 0.03. Despite the complex morphology of this relic, its subregions and the other isolated filaments also follow power-law behaviors, and show similar spectral slopes. Assuming diffusive shock acceleration, we estimated a dominant Mach number of ∼3.7 for the shocks that make up the relic. A comparison with recent numerical simulations suggests that in the case of radio relics, the slopes of the integrated radio spectra are determined by the Mach number of the accelerating shock, with α nearly constant, namely between -1.13 and -1.17, for Mach numbers 3.5 - 4.0. The spectral shapes inferred from spatially resolved regions show curvature, we speculate that the relic is inclined along the line of sight. The locus of points in the simulated color-color plots changes significantly with the relic viewing angle. We conclude that projection effects and inhomogeneities in the shock Mach number dominate the observed spectral properties of the relic in this complex system. Based on the new observations we raise the possibility that the relic and a narrow-angle-tailed radio galaxy are two different structures projected along the same line of sight.
Completing the 3CR Chandra Snapshot Survey: Extragalactic Radio Sources at High RedshiftJimenez-Gallardo, A.Massaro, F.Prieto, M. A.Missaglia, V.Stuardi, C.Paggi, A.Ricci, F.Kraft, Ralph P.Liuzzo, E.Tremblay, Grant R.Baum, S. A.O'Dea, C. P.Wilkes, Belinda J.Kuraszkiewicz, JoannaForman, William R.Harris, Dan E.DOI: info:10.3847/1538-4365/aba5a0v. 2507
Jimenez-Gallardo, A., Massaro, F., Prieto, M. A., Missaglia, V., Stuardi, C., Paggi, A., Ricci, F., Kraft, Ralph P., Liuzzo, E., Tremblay, Grant R., Baum, S. A., O'Dea, C. P., Wilkes, Belinda J., Kuraszkiewicz, Joanna, Forman, William R., and Harris, Dan E. 2020. "Completing the 3CR Chandra Snapshot Survey: Extragalactic Radio Sources at High Redshift." The Astrophysical Journal Supplement Series 250:7.
ID: 157477
Type: article
Authors: Jimenez-Gallardo, A.; Massaro, F.; Prieto, M. A.; Missaglia, V.; Stuardi, C.; Paggi, A.; Ricci, F.; Kraft, Ralph P.; Liuzzo, E.; Tremblay, Grant R.; Baum, S. A.; O'Dea, C. P.; Wilkes, Belinda J.; Kuraszkiewicz, Joanna; Forman, William R.; Harris, Dan E.
Abstract: We present the analysis of nine radio sources belonging to the Third Cambridge Revised catalog (3CR) observed with Chandra during Cycle 20 in the redshift range between 1.5 and 2.5. This study completes the 3CR Chandra Snapshot Survey thus guaranteeing the X-ray coverage of all 3CR sources identified to date. This sample lists two compact steep spectrum sources, four radio galaxies, and three quasars. We detected X-ray emission from all nuclei, with the only exception of 3C 326.1 and 3C 454.1 and from radio lobes in six out of nine sources at a level of confidence larger than ∼5σ. We measured X-ray fluxes and luminosities for all nuclei and lobes in the soft (0.5-1 keV), medium (1-2 keV), and hard (2-7 keV) X-ray bands. Since the discovered X-ray extended emission is spatially coincident with the radio structure in all cases, its origin could be due to inverse Compton (IC) scattering of the cosmic microwave background (CMB) occurring in radio lobes.
AGN feedback in the FR II galaxy 3C 220.1Liu, WenhaoSun, MingNulsen, Paul E. J.Worrall, Diana M.Birkinshaw, MarkSarazin, CraigForman, William R.Jones, ChristineGe, ChongDOI: info:10.1093/mnras/staa005v. 4923156–3168
Liu, Wenhao, Sun, Ming, Nulsen, Paul E. J., Worrall, Diana M., Birkinshaw, Mark, Sarazin, Craig, Forman, William R., Jones, Christine, and Ge, Chong. 2020. "AGN feedback in the FR II galaxy 3C 220.1." Monthly Notices of the Royal Astronomical Society 492:3156– 3168.
ID: 156376
Type: article
Authors: Liu, Wenhao; Sun, Ming; Nulsen, Paul E. J.; Worrall, Diana M.; Birkinshaw, Mark; Sarazin, Craig; Forman, William R.; Jones, Christine; Ge, Chong
Abstract: We present results from a deep (174 ks) Chandra observation of the FR-II radio galaxy 3C 220.1, the central brightest cluster galaxy (BCG) of a kT ∼ 4 keV cluster at z = 0.61. The temperature of the hot cluster medium drops from ∼5.9 to ∼3.9 keV at ∼35 kpc radius, while the temperature at smaller radii may be substantially lower. The central active galactic nucleus (AGN) outshines the whole cluster in X-rays, with a bolometric luminosity of 2.0 × 1046 erg s-1 (∼10 per cent of the Eddington rate). The system shows a pair of potential X-ray cavities ∼35 kpc east and west of the nucleus. The cavity power is estimated within the range of 1.0 × 1044 and 1.7 × 1045 erg s-1, from different methods. The X-ray enhancements in the radio lobes could be due to inverse Compton emission, with a total 2-10 keV luminosity of ∼8.0 × 1042 erg s-1. We compare 3C 220.1 with other cluster BCGs, including Cygnus A, as there are few BCGs in rich clusters hosting an FR-II galaxy. We also summarize the jet power of FR-II galaxies from different methods. The comparison suggests that the cavity power of FR-II galaxies likely underestimates the jet power. The properties of 3C 220.1 suggest that it is at the transition stage from quasar-mode feedback to radio- mode feedback.
Comparing different mass estimators for a large subsample of the Planck-ESZ clustersLovisari, LorenzoEttori, S.Sereno, M.Schellenberger, GerritForman, William R.Andrade-Santos, FelipeJones, C.DOI: info:10.1051/0004-6361/202038718v. 644A78
Lovisari, Lorenzo, Ettori, S., Sereno, M., Schellenberger, Gerrit, Forman, William R., Andrade-Santos, Felipe, and Jones, C. 2020. "Comparing different mass estimators for a large subsample of the Planck-ESZ clusters." Astronomy and Astrophysics 644:A78.
ID: 158594
Type: article
Authors: Lovisari, Lorenzo; Ettori, S.; Sereno, M.; Schellenberger, Gerrit; Forman, William R.; Andrade-Santos, Felipe; Jones, C.
Abstract: Context. Total mass is arguably the most fundamental property for cosmological studies with galaxy clusters. The individual cluster masses can be obtained with different methods, each with its own biases and limitations. Systematic differences in mass measurements can strongly impact the determination of the hydrostatic bias and of the mass-observable relations, key requirements of many cluster abundance studies.
Aims: We investigate the present differences in the mass estimates obtained through independent X-ray, weak-lensing, and dynamical studies using a large subsample of the Planck-ESZ clusters. We also discuss the implications for mass bias analyses.
Methods: After assessing the systematic differences in the X-ray-derived masses reported by distinct groups, we examine the mass estimates obtained with independent methods and quantify the differences as the mean ratio 1-b = MHE/MWL, dyn, where HE refers to hydrostatic masses obtained from X-ray observations, WL refers to the results of weak-lensing measurements, and dyn refers to the mass estimates either from velocity dispersion or from the caustic technique. So defined, the 1-b parameter includes all possible astrophysical, observational, and methodological biases in one single value.
Results: Recent X-ray masses reported by independent groups show average differences smaller than ˜10%, posing a strong limit on the systematics that can be ascribed to the differences in the X-ray analysis when studying the hydrostatic bias. The mean ratio between our X-ray masses and the weak-lensing masses in the LC2-single catalog is 1-b = 0.74 ± 0.06, which corresponds to a mass bias of 26 ± 6%, a value insufficient to reconcile the Planck cluster abundance and cosmic microwave background results. However, the mean mass ratios inferred from the WL masses of different projects vary by a large amount, with APEX-SZ showing a bias consistent with zero (1-b = 1.02 ± 0.12), LoCuSS and CCCP/MENeaCS showing a significant difference (1-b = 0.76 ± 0.09 and 1-b = 0.77 ± 0.10, respectively), and WtG pointing to the largest deviation (1-b = 0.61 ± 0.12), which would substantially reduce the tension between the Planck results. Because of small differences between our M - YX relation and the one used by the Planck collaboration, our X-ray masses are on average 7% lower (4% at the same physical radius) than the Planck masses and can further reduce the required bias. At odds with the WL results, the dynamical mass measurements show better agreement with the X-ray hydrostatic masses, although there are significant differences when relaxed or disturbed clusters are used. However, the comparison is currently limited by the small sample sizes. Conclisions. The systematic differences between total masses obtained with recent independent X-ray analyses are smaller than those found in previous studies. This shifts the focus to WL and dynamical studies for a better convergence of the level of mass bias. However, the ratios obtained using different mass estimators suggest that there are still systematics that are not accounted for in all the techniques used to recover cluster masses. This prevents the determination of firm constraints on the level of hydrostatic mass bias in galaxy clusters.
X-Ray Scaling Relations for a Representative Sample of Planck-selected Clusters Observed with XMM-NewtonLovisari, LorenzoSchellenberger, GerritSereno, MauroEttori, StefanoPratt, Gabriel W.Forman, William R.Jones, ChristineAndrade-Santos, FelipeRandall, ScottKraft, RalphDOI: info:10.3847/1538-4357/ab7997v. 892102
Lovisari, Lorenzo, Schellenberger, Gerrit, Sereno, Mauro, Ettori, Stefano, Pratt, Gabriel W., Forman, William R., Jones, Christine, Andrade-Santos, Felipe, Randall, Scott, and Kraft, Ralph. 2020. "X-Ray Scaling Relations for a Representative Sample of Planck-selected Clusters Observed with XMM-Newton." The Astrophysical Journal 892:102.
ID: 157289
Type: article
Authors: Lovisari, Lorenzo; Schellenberger, Gerrit; Sereno, Mauro; Ettori, Stefano; Pratt, Gabriel W.; Forman, William R.; Jones, Christine; Andrade-Santos, Felipe; Randall, Scott; Kraft, Ralph
Abstract: We report the scaling relations derived by fitting the X-ray parameters determined from analyzing the XMM-Newton observations of 120 galaxy clusters in the Planck Early Sunyaev-Zel'dovich (SZ) sample spanning the redshift range of 0.059 tot and L-T relations determined for different samples. Mtot-T, Mtot-YX, and Mtot-Mgas relations show little dependence on the dynamical state of the clusters, but the normalizations of these relations may depend on the mass range investigated. Although most of the clusters investigated in this work reside at relatively low redshift, the fits prefer values of γ, the parameter accounting for the redshift evolution, different from the self-similar predictions. This suggests an evolution ( relations show little dependence on the dynamical state of the clusters, but the normalizations of these relations may depend on the mass range investigated. Although most of the clusters investigated in this work reside at relatively low redshift, the fits prefer values of γ, the parameter accounting for the redshift evolution, different from the self-similar predictions. This suggests an evolution (tot-T relation) of the scaling relations. For the first time, we find significant evolution (>3σ) of the Mtot-T relation, pointing to an increase of the kinetic- to-thermal energy ratio with redshift. This is consistent with a scenario in which higher-redshift clusters are on average more disturbed than their lower-redshift counterparts.
The Chandra Deep Wide-field Survey: A New Chandra Legacy Survey in the Boötes Field. I. X-Ray Point Source Catalog, Number Counts, and Multiwavelength CounterpartsMasini, AlbertoHickox, Ryan C.Carroll, Christopher M.Aird, JamesAlexander, David M.Assef, Roberto J.Bower, RichardBrodwin, MarkBrown, Michael J. I.Chatterjee, SuchetanaChen, Chien-Ting J.Dey, ArjunDiPompeo, Michael A.Duncan, Kenneth J.Eisenhardt, Peter R. M.Forman, William R.Gonzalez, Anthony H.Goulding, Andrew D.Hainline, Kevin N.Jannuzi, Buell T.Jones, ChristineKochanek, Christopher S.Kraft, RalphLee, Kyoung-SooMiller, Eric D.Mullaney, JamesMyers, Adam D.Ptak, AndrewStanford, AdamStern, DanielVikhlinin, AlexeyWake, David A.Murray, Stephen S.DOI: info:10.3847/1538-4365/abb607v. 2512
Masini, Alberto, Hickox, Ryan C., Carroll, Christopher M., Aird, James, Alexander, David M., Assef, Roberto J., Bower, Richard, Brodwin, Mark, Brown, Michael J. I., Chatterjee, Suchetana, Chen, Chien-Ting J., Dey, Arjun, DiPompeo, Michael A., Duncan, Kenneth J., Eisenhardt, Peter R. M., Forman, William R., Gonzalez, Anthony H., Goulding, Andrew D., Hainline, Kevin N., Jannuzi, Buell T., Jones, Christine, Kochanek, Christopher S., Kraft, Ralph, Lee, Kyoung-Soo, Miller, Eric D. et al. 2020. "The Chandra Deep Wide-field Survey: A New Chandra Legacy Survey in the Boötes Field. I. X-Ray Point Source Catalog, Number Counts, and Multiwavelength Counterparts." The Astrophysical Journal Supplement Series 251:2.
ID: 158593
Type: article
Authors: Masini, Alberto; Hickox, Ryan C.; Carroll, Christopher M.; Aird, James; Alexander, David M.; Assef, Roberto J.; Bower, Richard; Brodwin, Mark; Brown, Michael J. I.; Chatterjee, Suchetana; Chen, Chien-Ting J.; Dey, Arjun; DiPompeo, Michael A.; Duncan, Kenneth J.; Eisenhardt, Peter R. M.; Forman, William R.; Gonzalez, Anthony H.; Goulding, Andrew D.; Hainline, Kevin N.; Jannuzi, Buell T.; Jones, Christine; Kochanek, Christopher S.; Kraft, Ralph; Lee, Kyoung-Soo; Miller, Eric D.; Mullaney, James; Myers, Adam D.; Ptak, Andrew; Stanford, Adam; Stern, Daniel; Vikhlinin, Alexey; Wake, David A.; Murray, Stephen S.
Abstract: We present a new, ambitious survey performed with the Chandra X-ray Observatory of the 9.3 deg2 Boötes field of the NOAO Deep Wide-Field Survey. The wide field probes a statistically representative volume of the universe at high redshift. The Chandra Deep Wide-field Survey exploits the excellent sensitivity and angular resolution of Chandra over a wide area, combining 281 observations spanning 15 yr, for a total exposure time of 3.4 Ms, and detects 6891 X-ray point sources down to limiting fluxes of 4.7 × 10-16, 1.5 × 10-16, and 9 ×10-16 erg cm-2 s-1 in the 0.5-7, 0.5-2, and 2-7 keV bands, respectively. The robustness and reliability of the detection strategy are validated through extensive, state-of-the-art simulations of the whole field. Accurate number counts, in good agreement with previous X-ray surveys, are derived thanks to the uniquely large number of point sources detected, which resolve 65.0% ± 12.8% of the cosmic X-ray background between 0.5 and 2 keV and 81.0% ± 11.5% between 2 and 7 keV. Exploiting the wealth of multiwavelength data available on the field, we assign redshifts to ˜94% of the X-ray sources, estimate their obscuration, and derive absorption-corrected luminosities. We provide an electronic catalog containing all of the relevant quantities needed for future investigations.
EAGLE and Illustris-TNG Predictions for Resolved eROSITA X-Ray Observations of the Circumgalactic Medium around Normal GalaxiesOppenheimer, Benjamin D.Bogdán, ÁkosCrain, Robert A.ZuHone, John A.Forman, William R.Schaye, JoopWijers, Nastasha A.Davies, Jonathan J.Jones, ChristineKraft, Ralph P.Ghirardini, VittorioDOI: info:10.3847/2041-8213/ab846fv. 893L24
Oppenheimer, Benjamin D., Bogdán, Ákos, Crain, Robert A., ZuHone, John A., Forman, William R., Schaye, Joop, Wijers, Nastasha A., Davies, Jonathan J., Jones, Christine, Kraft, Ralph P., and Ghirardini, Vittorio. 2020. "EAGLE and Illustris-TNG Predictions for Resolved eROSITA X-Ray Observations of the Circumgalactic Medium around Normal Galaxies." The Astrophysical Journal 893:L24.
ID: 157301
Type: article
Authors: Oppenheimer, Benjamin D.; Bogdán, Ákos; Crain, Robert A.; ZuHone, John A.; Forman, William R.; Schaye, Joop; Wijers, Nastasha A.; Davies, Jonathan J.; Jones, Christine; Kraft, Ralph P.; Ghirardini, Vittorio
Abstract: We simulate stacked observations of nearby hot X-ray coronae associated with galaxies in the EAGLE and Illustris-TNG hydrodynamic simulations. A forward modeling pipeline is developed to predict 4 yr eROSITA observations and stacked image analysis, including the effects of instrumental and astrophysical backgrounds. We propose an experiment to stack z ≍ 0.01 galaxies separated by specific star formation rate (sSFR) to examine how the hot (T ≥ 106 K) circumgalactic medium (CGM) differs for high- and low-sSFR galaxies. The simulations indicate that the hot CGM of low-mass ( ${M}_{* }\approx {10}^{10.5}\ {M}_{\odot }$ ), high-sSFR (defined as the top one-third ranked by sSFR) central galaxies will be detectable to a galactocentric radius r ≍ 30-50 kpc. Both simulations predict lower luminosities at fixed stellar mass for the low-sSFR galaxies (the lower third of sSFR) with Illustris-TNG predicting 3× brighter coronae around high-sSFR galaxies than EAGLE. Both simulations predict detectable emission out to r ≍ 150-200 kpc for stacks centered on high-mass ( ${M}_{* }\approx {10}^{11.0}\ {M}_{\odot }$ ) galaxies, with EAGLE predicting brighter X-ray halos. The extended soft X-ray luminosity correlates strongly and positively with the mass of circumgalactic gas within the virial radius (fCGM). Prior analyses of both simulations have established that fCGM is reduced by expulsive feedback driven mainly by black hole growth, which quenches galaxy growth by inhibiting replenishment of the interstellar medium. Both simulations predict that eROSITA stacks should not only conclusively detect and resolve the hot CGM around L* galaxies for the first time, but provide a powerful probe of how the baryon cycle operates, for which there remains an absence of consensus between state- of-the-art simulations.
Atacama Compact Array Measurements of the Molecular Mass in the NGC 5044 Cooling-flow GroupSchellenberger, GerritDavid, Laurence P.Vrtilek, JanO'Sullivan, EwanLim, JeremyForman, WilliamSun, MingCombes, FrancoiseSalome, PhilippeJones, ChristineGiacintucci, SimonaEdge, AlastairGastaldello, FabioTemi, PasqualeBrighenti, FabrizioBardelli, SandroDOI: info:10.3847/1538-4357/ab879cv. 89472
Schellenberger, Gerrit, David, Laurence P., Vrtilek, Jan, O'Sullivan, Ewan, Lim, Jeremy, Forman, William, Sun, Ming, Combes, Francoise, Salome, Philippe, Jones, Christine, Giacintucci, Simona, Edge, Alastair, Gastaldello, Fabio, Temi, Pasquale, Brighenti, Fabrizio, and Bardelli, Sandro. 2020. "Atacama Compact Array Measurements of the Molecular Mass in the NGC 5044 Cooling-flow Group." The Astrophysical Journal 894:72.
ID: 156917
Type: article
Authors: Schellenberger, Gerrit; David, Laurence P.; Vrtilek, Jan; O'Sullivan, Ewan; Lim, Jeremy; Forman, William; Sun, Ming; Combes, Francoise; Salome, Philippe; Jones, Christine; Giacintucci, Simona; Edge, Alastair; Gastaldello, Fabio; Temi, Pasquale; Brighenti, Fabrizio; Bardelli, Sandro
Abstract: The fate of cooling gas in the centers of galaxy clusters and groups is still not well understood, as is also the case for the complex processes of triggering star formation in central dominant galaxies, reheating of cooled gas by active galactic nuclei (AGN), and the triggering or "feeding" of supermassive black hole outbursts. We present CO observations of the early-type galaxy NGC 5044, which resides at the center of an X-ray bright group with a moderate cooling flow. For our analysis we combine CO(2-1) data from the 7 m antennae of the Atacama Compact Array (ACA) and the ACA total power array (TP). We demonstrate, using the 7 m array data, that we can recover the total flux inferred from IRAM 30 m single-dish observations, which corresponds to a total molecular mass of about 4 × 107M. Most of the recovered flux is blueshifted with respect to the galaxy rest frame and is extended on kiloparsec-scales, suggesting low filling factor dispersed clouds. We find eight concentrations of molecular gas out to a radius of 10″ (1.5 kpc), which we identify with giant molecular clouds. The total molecular gas mass is more centrally concentrated than the X-ray emitting gas, but is extended in the northeast-southwest direction beyond the IRAM 30 m beam. We also compare the spatial extent of the molecular gas to the Hα emission: The CO emission coincides with the very bright Hα region in the center. We do not detect CO emission in the fainter Hα regions. Furthermore, we find two CO absorption features spatially located at the center of the galaxy, within 5 pc projected distance of the AGN, infalling at 255 and 265 km s-1 relative to the AGN. This indicates that the two giant molecular clouds seen in absorption are most likely within the sphere of influence of the supermassive black hole.
A deep learning view of the census of galaxy clusters in IllustrisTNGSu, Y.Zhang, Y.Liang, G.ZuHone, John A.Barnes, D. J.Jacobs, N. B.Ntampaka, MichelleForman, William R.Nulsen, Paul E. J.Kraft, Ralph P.Jones, C.DOI: info:10.1093/mnras/staa2690v. 4985620–5628
Su, Y., Zhang, Y., Liang, G., ZuHone, John A., Barnes, D. J., Jacobs, N. B., Ntampaka, Michelle, Forman, William R., Nulsen, Paul E. J., Kraft, Ralph P., and Jones, C. 2020. "A deep learning view of the census of galaxy clusters in IllustrisTNG." Monthly Notices of the Royal Astronomical Society 498:5620– 5628.
ID: 158586
Type: article
Authors: Su, Y.; Zhang, Y.; Liang, G.; ZuHone, John A.; Barnes, D. J.; Jacobs, N. B.; Ntampaka, Michelle; Forman, William R.; Nulsen, Paul E. J.; Kraft, Ralph P.; Jones, C.
Abstract: The origin of the diverse population of galaxy clusters remains an unexplained aspect of large-scale structure formation and cluster evolution. We present a novel method of using X-ray images to identify cool core (CC), weak cool core (WCC), and non-cool core (NCC) clusters of galaxies that are defined by their central cooling times. We employ a convolutional neural network, ResNet-18, which is commonly used for image analysis, to classify clusters. We produce mock Chandra X-ray observations for a sample of 318 massive clusters drawn from the IllustrisTNG simulations. The network is trained and tested with low-resolution mock Chandra images covering a central 1 Mpc square for the clusters in our sample. Without any spectral information, the deep learning algorithm is able to identify CC, WCC, and NCC clusters, achieving balanced accuracies (BAcc) of 92 per cent, 81 per cent, and 83 per cent, respectively. The performance is superior to classification by conventional methods using central gas densities, with an average ${\rm BAcc}=81{{\ \rm per\ cent}}$ , or surface brightness concentrations, giving ${\rm BAcc}=73{{\ \rm per\ cent}}$ . We use class activation mapping to localize discriminative regions for the classification decision. From this analysis, we observe that the network has utilized regions from cluster centres out to r ? 300 kpc and r ? 500 kpc to identify CC and NCC clusters, respectively. It may have recognized features in the intracluster medium that are associated with AGN feedback and disruptive major mergers.
The discovery of radio halos in the frontier fields clusters Abell S1063 and Abell 370Xie, C.van Weeren, Reinout J.Lovisari, L.Andrade-Santos, FelipeBotteon, A.Brüggen, M.Bulbul, EsraChurazov, E.Clarke, T. E.Forman, William R.Intema, H. T.Jones, C.Kraft, Ralph P.Lal, D. V.Mroczkowski, T.Zitrin, A.DOI: info:10.1051/0004-6361/201936953v. 636A3
Xie, C., van Weeren, Reinout J., Lovisari, L., Andrade-Santos, Felipe, Botteon, A., Brüggen, M., Bulbul, Esra, Churazov, E., Clarke, T. E., Forman, William R., Intema, H. T., Jones, C., Kraft, Ralph P., Lal, D. V., Mroczkowski, T., and Zitrin, A. 2020. "The discovery of radio halos in the frontier fields clusters Abell S1063 and Abell 370." Astronomy and Astrophysics 636:A3.
ID: 156987
Type: article
Authors: Xie, C.; van Weeren, Reinout J.; Lovisari, L.; Andrade-Santos, Felipe; Botteon, A.; Brüggen, M.; Bulbul, Esra; Churazov, E.; Clarke, T. E.; Forman, William R.; Intema, H. T.; Jones, C.; Kraft, Ralph P.; Lal, D. V.; Mroczkowski, T.; Zitrin, A.
Abstract: Context. Massive merging galaxy clusters often host diffuse megaparsec- scale radio synchrotron emission. This emission originates from relativistic electrons in the ionized intracluster medium. An important question is how these synchrotron emitting relativistic electrons are accelerated.
Aims: Our aim is to search for diffuse emission in the Frontier Fields clusters Abell S1063 and Abell 370 and characterize its properties. While these clusters are very massive and well studied at some other wavelengths, no diffuse emission has been reported for these clusters so far.
Methods: We obtained 325 MHz Giant Metrewave Radio Telescope (GMRT) and 1-4 GHz Jansky Very Large Array (VLA) observations of Abell S1063 and Abell 370. We complement these data with Chandra and XMM-Newton X-ray observations.
Results: In our sensitive images, we discover radio halos in both clusters. In Abell S1063, a giant radio halo is found with a size of ∼1.2 Mpc. The integrated spectral index between 325 MHz and 1.5 GHz is -0.94 ± 0.08 and it steepens to -1.77 ± 0.20 between 1.5 and 3.0 GHz. This spectral steepening provides support for the turbulent reacceleration model for radio halo formation. Abell 370 hosts a faint radio halo mostly centered on the southern part of this binary merging cluster, with a size of ∼500-700 kpc. The spectral index between 325 MHz and 1.5 GHz is -1.10 ± 0.09. Both radio halos follow the known scaling relation between the cluster mass proxy Y500 and radio power, which is consistent with the idea that they are related to ongoing cluster merger events.
Collision of merger and accretion shocks: formation of Mpc-scale contact discontinuity in the Perseus clusterZhang, CongyaoChurazov, EugeneDolag, KlausForman, William R.Zhuravleva, IrinaDOI: info:10.1093/mnrasl/slaa147v. 498L130–L134
Zhang, Congyao, Churazov, Eugene, Dolag, Klaus, Forman, William R., and Zhuravleva, Irina. 2020. "Collision of merger and accretion shocks: formation of Mpc-scale contact discontinuity in the Perseus cluster." Monthly Notices of the Royal Astronomical Society 498:L130– L134.
ID: 157774
Type: article
Authors: Zhang, Congyao; Churazov, Eugene; Dolag, Klaus; Forman, William R.; Zhuravleva, Irina
Abstract: Two Mpc-size contact discontinuities have recently been identified in the XMM-Newton and Suzaku X-ray observations in the outskirts of the Perseus cluster (Walker et al.). These structures have been tentatively interpreted as 'sloshing cold fronts', which are customarily associated with differential motions of the cluster gas, perturbed by a merger. In this study, we consider an alternative scenario, namely, that the most prominent discontinuity, near the cluster virial radius, is the result of the collision between the accretion shock and a 'runaway' merger shock. We also discuss the possible origin of the second discontinuity at ${\sim}1.2{\rm \, Mpc}$ .
Encounters of merger and accretion shocks in galaxy clusters and their effects on intracluster mediumZhang, CongyaoChurazov, EugeneDolag, KlausForman, William R.Zhuravleva, IrinaDOI: info:10.1093/mnras/staa1013v. 4944539–4547
Zhang, Congyao, Churazov, Eugene, Dolag, Klaus, Forman, William R., and Zhuravleva, Irina. 2020. "Encounters of merger and accretion shocks in galaxy clusters and their effects on intracluster medium." Monthly Notices of the Royal Astronomical Society 494:4539– 4547.
ID: 157775
Type: article
Authors: Zhang, Congyao; Churazov, Eugene; Dolag, Klaus; Forman, William R.; Zhuravleva, Irina
Abstract: Several types/classes of shocks naturally arise during formation and evolution of galaxy clusters. One such class is represented by accretion shocks, associated with deceleration of infalling baryons. Such shocks, characterized by a very high Mach number, are present even in 1D models of cluster evolution. Another class is composed of 'runaway merger shocks', which appear when a merger shock, driven by a sufficiently massive infalling subcluster, propagates away from the main-cluster centre. We argue that, when the merger shock overtakes the accretion shock, a new long-living shock is formed that propagates to large distances from the main cluster (well beyond its virial radius), affecting the cold gas around the cluster. We refer to these structures as Merger-accelerated Accretion shocks (MA-shocks) in this paper. We show examples of such MA-shocks in one-dimensioanal (1D) and three-dimensional (3D) simulations and discuss their characteristic properties. In particular, (1) MA-shocks shape the boundary separating the hot intracluster medium (ICM) from the unshocked gas, giving this boundary a 'flower-like' morphology. In 3D, MA-shocks occupy space between the dense accreting filaments. (2) Evolution of MA-shocks highly depends on the Mach number of the runaway merger shock and the mass accretion rate parameter of the cluster. (3) MA-shocks may lead to the misalignment of the ICM boundary and the splashback radius.
Chandra Observations of the Spectacular A3411─12 Merger EventAndrade-Santos, Felipevan Weeren, Reinout J.Di Gennaro, GabriellaWittman, DavidRyu, DongsuVir Lal, DharamPlacco, Vinicius M.Fogarty, KevinJee, M. JamesStroe, AndraSobral, DavidForman, William R.Jones, ChristineKraft, Ralph P.Murray, Stephen S.Brüggen, MarcusKang, HyesungSantucci, RafaelGolovich, NathanDawson, WilliamDOI: info:10.3847/1538-4357/ab4ce5v. 88731
Andrade-Santos, Felipe, van Weeren, Reinout J., Di Gennaro, Gabriella, Wittman, David, Ryu, Dongsu, Vir Lal, Dharam, Placco, Vinicius M., Fogarty, Kevin, Jee, M. James, Stroe, Andra, Sobral, David, Forman, William R., Jones, Christine, Kraft, Ralph P., Murray, Stephen S., Brüggen, Marcus, Kang, Hyesung, Santucci, Rafael, Golovich, Nathan, and Dawson, William. 2019. "Chandra Observations of the Spectacular A3411─12 Merger Event." The Astrophysical Journal 887:31.
ID: 154553
Type: article
Authors: Andrade-Santos, Felipe; van Weeren, Reinout J.; Di Gennaro, Gabriella; Wittman, David; Ryu, Dongsu; Vir Lal, Dharam; Placco, Vinicius M.; Fogarty, Kevin; Jee, M. James; Stroe, Andra; Sobral, David; Forman, William R.; Jones, Christine; Kraft, Ralph P.; Murray, Stephen S.; Brüggen, Marcus; Kang, Hyesung; Santucci, Rafael; Golovich, Nathan; Dawson, William
Abstract: We present deep Chandra observations of A3411─12, a remarkable merging cluster that hosts the most compelling evidence for electron reacceleration at cluster shocks to date. Using the {Y}{{X}}{--}M scaling relation, we find r 500 ∼ 1.3 Mpc, {M}500=(7.1+/- 0.7)× {10}14 {M}ȯ , {kT}=6.5+/- 0.1 {keV}, and a gas mass of {M}{{g},500}=(9.7+/- 0.1)× {10}13{M}ȯ . The gas mass fraction within r 500 is {f}{{g}}=0.14+/- 0.01. We compute the shock strength using density jumps to conclude that the Mach number of the merging subcluster is small (M≤slant {1.15}-0.09+0.14). We also present density, temperature, pseudo-pressure, and pseudo-entropy maps. Based on the pseudo-entropy map, we conclude that the cluster is undergoing a mild merger, consistent with the small Mach number. On the other hand, radio relics extend over Mpc scale in the A3411─12 system, which strongly suggests that a population of energetic electrons already existed over extended regions of the cluster.
Cluster Cosmology Constraints from the 2500 deg2 SPT-SZ Survey: Inclusion of Weak Gravitational Lensing Data from Magellan and the Hubble Space TelescopeBocquet, S.Dietrich, J. P.Schrabback, T.Bleem, L. E.Klein, M.Allen, S. W.Applegate, D. E.Ashby, Matthew L. N.Bautz, M.Bayliss, M.Benson, B. A.Brodwin, M.Bulbul, EsraCanning, R. E. A.Capasso, R.Carlstrom, J. E.Chang, C. L.Chiu, I.Cho, H. -MClocchiatti, A.Crawford, T. M.Crites, A. Haan, T.Desai, S.Dobbs, M. A.Foley, R. J.Forman, William R.Garmire, G. P.George, E. M.Gladders, M. D.Gonzalez, A. H.Grandis, S.Gupta, N.Halverson, N. W.Hlavacek-Larrondo, J.Hoekstra, H.Holder, G. P.Holzapfel, W. L.Hou, Z.Hrubes, J. D.Huang, N.Jones, ChristineKhullar, G.Knox, L.Kraft, RalphLee, A. T.von der Linden, A.Luong-Van, D.Mantz, A.Marrone, D. P.McDonald, M.McMahon, J. J.Meyer, S. S.Mocanu, L. M.Mohr, J. J.Morris, R. G.Padin, S.Patil, S.Pryke, C.Rapetti, D.Reichardt, C. L.Rest, A.Ruhl, J. E.Saliwanchik, B. R.Saro, A.Sayre, J. T.Schaffer, K. K.Shirokoff, E.Stalder, BrianStanford, S. A.Staniszewski, Z.Stark, Antony A.Story, K. T.Strazzullo, V.Stubbs, Christopher W.Vanderlinde, K.Vieira, J. D.Vikhlinin, AlexeyWilliamson, R.Zenteno, A.DOI: info:10.3847/1538-4357/ab1f10v. 87855
Bocquet, S., Dietrich, J. P., Schrabback, T., Bleem, L. E., Klein, M., Allen, S. W., Applegate, D. E., Ashby, Matthew L. N., Bautz, M., Bayliss, M., Benson, B. A., Brodwin, M., Bulbul, Esra, Canning, R. E. A., Capasso, R., Carlstrom, J. E., Chang, C. L., Chiu, I., Cho, H. -M, Clocchiatti, A., Crawford, T. M., Crites, A. T., de Haan, T., Desai, S., Dobbs, M. A. et al. 2019. "Cluster Cosmology Constraints from the 2500 deg2 SPT-SZ Survey: Inclusion of Weak Gravitational Lensing Data from Magellan and the Hubble Space Telescope." The Astrophysical Journal 878:55.
ID: 155151
Type: article
Authors: Bocquet, S.; Dietrich, J. P.; Schrabback, T.; Bleem, L. E.; Klein, M.; Allen, S. W.; Applegate, D. E.; Ashby, Matthew L. N.; Bautz, M.; Bayliss, M.; Benson, B. A.; Brodwin, M.; Bulbul, Esra; Canning, R. E. A.; Capasso, R.; Carlstrom, J. E.; Chang, C. L.; Chiu, I.; Cho, H. -M; Clocchiatti, A.; Crawford, T. M.; Crites, A. T.; de Haan, T.; Desai, S.; Dobbs, M. A.; Foley, R. J.; Forman, William R.; Garmire, G. P.; George, E. M.; Gladders, M. D.; Gonzalez, A. H.; Grandis, S.; Gupta, N.; Halverson, N. W.; Hlavacek-Larrondo, J.; Hoekstra, H.; Holder, G. P.; Holzapfel, W. L.; Hou, Z.; Hrubes, J. D.; Huang, N.; Jones, Christine; Khullar, G.; Knox, L.; Kraft, Ralph; Lee, A. T.; von der Linden, A.; Luong-Van, D.; Mantz, A.; Marrone, D. P.; McDonald, M.; McMahon, J. J.; Meyer, S. S.; Mocanu, L. M.; Mohr, J. J.; Morris, R. G.; Padin, S.; Patil, S.; Pryke, C.; Rapetti, D.; Reichardt, C. L.; Rest, A.; Ruhl, J. E.; Saliwanchik, B. R.; Saro, A.; Sayre, J. T.; Schaffer, K. K.; Shirokoff, E.; Stalder, Brian; Stanford, S. A.; Staniszewski, Z.; Stark, Antony A.; Story, K. T.; Strazzullo, V.; Stubbs, Christopher W.; Vanderlinde, K.; Vieira, J. D.; Vikhlinin, Alexey; Williamson, R.; Zenteno, A.
Abstract: We derive cosmological constraints using a galaxy cluster sample selected from the 2500 deg2 SPT-SZ survey. The sample spans the redshift range 0.25 SPT-SZ survey. The sample spans the redshift range 0.25 5. The sample is supplemented with optical weak gravitational lensing measurements of 32 clusters with 0.29 5. The sample is supplemented with optical weak gravitational lensing measurements of 32 clusters with 0.29 5. The sample is supplemented with optical weak gravitational lensing measurements of 32 clusters with 0.29 5. The sample is supplemented with optical weak gravitational lensing measurements of 32 clusters with 0.29 5. The sample is supplemented with optical weak gravitational lensing measurements of 32 clusters with 0.29 m = 0.276 ± 0.047, σ 8 = 0.781 ± 0.037, and σ 8m/0.3)0.2 = 0.766 ±0.025. The redshift evolutions of the X-ray Y X-mass and M gas-mass relations are both consistent with self-similar evolution to within 1σ. The mass slope of the Y X-mass relation shows a 2.3σ deviation from self-similarity. Similarly, the mass slope of the M gas-mass relation is steeper than self- similarity at the 2.5σ level. In a νwCDM cosmology, we measure the dark energy equation-of-state parameter w = -1.55 ± 0.41 from the cluster data. We perform a measurement of the growth of structure since redshift z ∼ 1.7 and find no evidence for tension with the prediction from general relativity. This is the first analysis of the SPT cluster sample that uses direct weak-lensing mass calibration and is a step toward using the much larger weak-lensing data set from DES. We provide updated redshift and mass estimates for the SPT sample.
X-Ray Properties of SPT-selected Galaxy Clusters at 0.2 < z < 1.5 Observed with XMM-NewtonBulbul, EsraChiu, I. -nonMohr, Joseph J.McDonald, MichaelBenson, BradfordBautz, Mark W.Bayliss, MatthewBleem, LindseyBrodwin, MarkBocquet, SebastianCapasso, RaffaellaDietrich, Jörg P.Forman, BillHlavacek-Larrondo, JulieHolzapfel, W. L.Khullar, GouravKlein, MatthiasKraft, RalphMiller, Eric D.Reichardt, ChristianSaro, AlexSharon, KerenStalder, BrianSchrabback, TimStanford, AdamDOI: info:10.3847/1538-4357/aaf230v. 87150
Bulbul, Esra, Chiu, I. -non, Mohr, Joseph J., McDonald, Michael, Benson, Bradford, Bautz, Mark W., Bayliss, Matthew, Bleem, Lindsey, Brodwin, Mark, Bocquet, Sebastian, Capasso, Raffaella, Dietrich, Jörg P., Forman, Bill, Hlavacek-Larrondo, Julie, Holzapfel, W. L., Khullar, Gourav, Klein, Matthias, Kraft, Ralph, Miller, Eric D., Reichardt, Christian, Saro, Alex, Sharon, Keren, Stalder, Brian, Schrabback, Tim, and Stanford, Adam. 2019. "X-Ray Properties of SPT-selected Galaxy Clusters at 0.2 < z < 1.5 Observed with XMM-Newton." The Astrophysical Journal 871:50.
ID: 150433
Type: article
Authors: Bulbul, Esra; Chiu, I. -non; Mohr, Joseph J.; McDonald, Michael; Benson, Bradford; Bautz, Mark W.; Bayliss, Matthew; Bleem, Lindsey; Brodwin, Mark; Bocquet, Sebastian; Capasso, Raffaella; Dietrich, Jörg P.; Forman, Bill; Hlavacek-Larrondo, Julie; Holzapfel, W. L.; Khullar, Gourav; Klein, Matthias; Kraft, Ralph; Miller, Eric D.; Reichardt, Christian; Saro, Alex; Sharon, Keren; Stalder, Brian; Schrabback, Tim; Stanford, Adam
Abstract: We present measurements of the X-ray observables of the intracluster medium (ICM), including luminosity L X , ICM mass M ICM, emission-weighted mean temperature T X , and integrated pressure Y X , that are derived from XMM-Newton X-ray observations of a Sunyaev–Zel’dovich effect (SZE) selected sample of 59 galaxy clusters from the South Pole Telescope SPT-SZ survey that span the redshift range 0.20 , that are derived from XMM-Newton X-ray observations of a Sunyaev–Zel’dovich effect (SZE) selected sample of 59 galaxy clusters from the South Pole Telescope SPT-SZ survey that span the redshift range 0.20 , that are derived from XMM-Newton X-ray observations of a Sunyaev–Zel’dovich effect (SZE) selected sample of 59 galaxy clusters from the South Pole Telescope SPT-SZ survey that span the redshift range 0.20 500 ≥ 3 × 1014 M ) to the highest redshifts where these clusters exist without concern for X-ray selection biases. We find that the mass trends are steeper than self-similarity in all cases, and with ≥2.5σ significance in the case of L X and M ICM. The redshift trends are consistent with the self-similar expectation, but the uncertainties remain large. Core-included scaling relations tend to have steeper mass trends for L X . There is no convincing evidence for a redshift-dependent mass trend in any observable. The constraints on the amplitudes of the fitted scaling relations are currently limited by the systematic uncertainties on the SZE-based halo masses, but the redshift and mass trends are limited by the X-ray sample size and the measurement uncertainties of the X-ray observables.
Evidence for a Merger-induced Shock Wave in ZwCl 0008.8+5215 with Chandra and SuzakuDi Gennaro, Gabriellavan Weeren, Reinout J.Andrade-Santos, FelipeAkamatsu, H.Randall, Scott W.Forman, William R.Kraft, Ralph P.Brunetti, G.Dawson, W. A.Golovich, N.Jones, ChristineDOI: info:10.3847/1538-4357/ab03cdv. 87364
Di Gennaro, Gabriella, van Weeren, Reinout J., Andrade-Santos, Felipe, Akamatsu, H., Randall, Scott W., Forman, William R., Kraft, Ralph P., Brunetti, G., Dawson, W. A., Golovich, N., and Jones, Christine. 2019. "Evidence for a Merger-induced Shock Wave in ZwCl 0008.8+5215 with Chandra and Suzaku." The Astrophysical Journal 873:64.
ID: 150904
Type: article
Authors: Di Gennaro, Gabriella; van Weeren, Reinout J.; Andrade-Santos, Felipe; Akamatsu, H.; Randall, Scott W.; Forman, William R.; Kraft, Ralph P.; Brunetti, G.; Dawson, W. A.; Golovich, N.; Jones, Christine
Abstract: We present the results from new deep Chandra (∼410 ks) and Suzaku (∼180 ks) observations of the merging galaxy cluster ZwCl 0008.8+5215 (z = 0.104). Previous radio observations revealed the presence of a double radio relic located diametrically west and east of the cluster center. Using our new Chandra data, we find evidence for the presence of a shock at the location of the western relic, RW, with a Mach number {{ \mathcal M }}{SX}={1.48}-0.32+0.50 from the density jump. We also measure {{ \mathcal M }}{TX}={2.35}-0.55+0.74 and {{ \mathcal M }}{TX}={2.02}-0.47+0.74 from the temperature jump, with Chandra and Suzaku, respectively. These values are consistent with the Mach number estimate from a previous study of the radio spectral index, under the assumption of diffusive shock acceleration ({{ \mathcal M }}RW}={2.4}-0.2+0.4). Interestingly, the western radio relic does not entirely trace the X-ray shock. A possible explanation is that the relic traces fossil plasma from nearby radio galaxies that is reaccelerated at the shock. For the eastern relic we do not detect an X-ray surface brightness discontinuity, despite the fact that radio observations suggest a shock with {{ \mathcal M }}RE}={2.2}-0.1+0.2. The low surface brightness and reduced integration time for this region might have prevented the detection. The Chandra surface brightness profile suggests { \mathcal M }≲ 1.5, while the Suzaku temperature measurements found {{ \mathcal M }}{TX}={1.54}-0.47+0.65. Finally, we also detect a merger-induced cold front on the western side of the cluster, behind the shock that traces the western relic.
A merger shock in Abell 1367Ge, ChongSun, MingLiu, Ruo-YuRudnick, LawrenceSarazin, CraigForman, WilliamJones, ChristineChen, HaoLiu, WenhaoYagi, MasafumiBoselli, AlessandroFossati, MatteoGavazzi, GiuseppeDOI: info:10.1093/mnrasl/slz049v. 486L36–L40
Ge, Chong, Sun, Ming, Liu, Ruo-Yu, Rudnick, Lawrence, Sarazin, Craig, Forman, William, Jones, Christine, Chen, Hao, Liu, Wenhao, Yagi, Masafumi, Boselli, Alessandro, Fossati, Matteo, and Gavazzi, Giuseppe. 2019. "A merger shock in Abell 1367." Monthly Notices of the Royal Astronomical Society 486:L36– L40.
ID: 152897
Type: article
Authors: Ge, Chong; Sun, Ming; Liu, Ruo-Yu; Rudnick, Lawrence; Sarazin, Craig; Forman, William; Jones, Christine; Chen, Hao; Liu, Wenhao; Yagi, Masafumi; Boselli, Alessandro; Fossati, Matteo; Gavazzi, Giuseppe
Abstract: Multiwavelength observations show that Abell 1367 (A1367) is a dynamically young cluster, with at least two subclusters merging along the SE-NW direction. With the wide-field XMM-Newton mosaic of A1367, we discover a previously unknown merger shock at the NW edge of the cluster. We estimate the shock Mach number from the density and temperature jumps as Mρ = 1.21 ± 0.08 and MT = 1.60 ± 0.07, respectively. This shock region also corresponds to a radio relic discovered with the VLA and GBT, which could be produced by the shock re-acceleration of pre-existing seed relativistic electrons. We suggest that some of the seed relativistic electrons originate from late-type, star-forming galaxies in this region.
X-ray scaling relations from a complete sample of the richest maxBCG clustersGe, ChongSun, MingRozo, EduardoSehgal, NeelimaVikhlinin, AlexeyForman, WilliamJones, ChristineNagai, DaisukeDOI: info:10.1093/mnras/stz088v. 4841946–1971
Ge, Chong, Sun, Ming, Rozo, Eduardo, Sehgal, Neelima, Vikhlinin, Alexey, Forman, William, Jones, Christine, and Nagai, Daisuke. 2019. "X-ray scaling relations from a complete sample of the richest maxBCG clusters." Monthly Notices of the Royal Astronomical Society 484:1946– 1971.
ID: 151208
Type: article
Authors: Ge, Chong; Sun, Ming; Rozo, Eduardo; Sehgal, Neelima; Vikhlinin, Alexey; Forman, William; Jones, Christine; Nagai, Daisuke
Abstract: We use a complete sample of 38 richest maxBCG clusters to study the ICM-galaxy scaling relations and the halo mass selection properties of the maxBCG algorithm, based on X-ray and optical observations. The clusters are selected from the two largest bins of optical richness in the Planck stacking work with the maxBCG richness N200 ≥ 78. We analyse their Chandra and XMM-Newton data to derive the X-ray properties of the ICM. We then use the distribution of P(X|N), X = TX, LX, YX, to study the mass selection P(M|N) of maxBCG. Compared with previous works based on the whole richness sample, a significant fraction of blended systems with boosted richness is skewed into this richest sample. Parts of the blended haloes are picked apart by the redMaPPer, an updated red-sequence cluster finding algorithm with lower mass scatter. Moreover, all the optical blended haloes are resolved as individual X-ray haloes, following the established LX-TX and LX-YX relations. We further discuss that the discrepancy between ICM-galaxy scaling relations, especially for future blind stacking, can come from several factors, including miscentring, projection, contamination of low-mass systems, mass bias, and covariance bias. We also evaluate the fractions of relaxed and cool core clusters in our sample. Both are smaller than those from SZ or X-ray selected samples. Moreover, disturbed clusters show a higher level of mass bias than relaxed clusters.