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Full-Text Articles in Physical Sciences and Mathematics
Cosmology-Independent Estimate Of The Fraction Of Baryon Mass In The Igm From Fast Radio Burst Observations, Zhengxiang Li, He Gao, Jun-Jie Wei, Yuan-Pei Yang, Bing Zhang, Zong-Hong Zhu
Cosmology-Independent Estimate Of The Fraction Of Baryon Mass In The Igm From Fast Radio Burst Observations, Zhengxiang Li, He Gao, Jun-Jie Wei, Yuan-Pei Yang, Bing Zhang, Zong-Hong Zhu
Physics & Astronomy Faculty Research
The excessive dispersion measure (DM) of fast radio bursts (FRBs) has been proposed to be a powerful tool to study intergalactic medium (IGM) and to perform cosmography. One issue is that the fraction of baryons in the IGM, f IGM, is not properly constrained. Here, we propose a method of estimating f IGM using a putative sample of FRBs with the measurements of both DM and luminosity distance d L. The latter can be obtained if the FRB is associated with a distance indicator (e.g., a gamma-ray burst or a gravitational-wave event), or the redshift z of the FRB is …
The Dependence Of Intrinsic Alignment Of Galaxies On Wavelength Using Kids And Gama, Christos Georgiou, Harry Johnston, Henk Hoekstra, Massimo Viola, Konrad Kuijken, Benjamin Joachimi, Nora Elisa Chisari, Daniel J. Farrow, Hendrik Hildebrandt, Benne W. Holwerda, Arun Kannawadi
The Dependence Of Intrinsic Alignment Of Galaxies On Wavelength Using Kids And Gama, Christos Georgiou, Harry Johnston, Henk Hoekstra, Massimo Viola, Konrad Kuijken, Benjamin Joachimi, Nora Elisa Chisari, Daniel J. Farrow, Hendrik Hildebrandt, Benne W. Holwerda, Arun Kannawadi
Faculty Scholarship
The outer regions of galaxies are more susceptible to the tidal interactions that lead to intrinsic alignments of galaxies. The resulting alignment signal may therefore depend on the passband if the colours of galaxies vary spatially. To quantify this, we measured the shapes of galaxies with spectroscopic redshifts from the GAMA survey using deep gri imaging data from the KiloDegree Survey. The performance of the moment-based shape measurement algorithm DEIMOS was assessed using dedicated image simulations, which showed that the ellipticities could be determined with an accuracy better than 1% in all bands. Additional tests for potential systematic errors did …
Testing For Directionality In The Planck Polarization And Lensing Data, Majd Ghrear, Emory F. Bunn, Dagoberto Contreras, Douglas Scott
Testing For Directionality In The Planck Polarization And Lensing Data, Majd Ghrear, Emory F. Bunn, Dagoberto Contreras, Douglas Scott
Physics Faculty Publications
In order to better analyse the polarization of the cosmic microwave background (CMB), which is dominated by emission from our Galaxy, we need tools that can detect residual foregrounds in cleaned CMB maps. Galactic foregrounds introduce statistical anisotropy and directionality to the polarization pseudo-vectors of the CMB, which can be investigated by using the D statistic of Bunn and Scott. This statistic is rapidly computable and capable of investigating a broad range of data products for directionality. We demonstrate the application of this statistic to detecting foregrounds in polarization maps by analysing the uncleaned Planck 2018 frequency maps. For the …
The Dark Energy Survey Image Processing Pipeline, E. Morganson, R. A. Gruendl, F. Menanteau, M. Carrasco Kind, Y.-C. Chen, G. Daues, A. Drlica-Wagner, D. N. Friedel, M. Gower, M. W. G. Johnson, M. D. Johnson, R. Kessler, F. Paz-Chinchón, D. Petravick, C. Pond, B. Yanny, S. Allam, R. Armstrong, Wayne A. Barkhouse, K. Bechtol, A. Benoit-Lévy, G. M. Bernstein, E. Bertin, E. Buckley-Geer, R. Covarrubias, S. Desai, H. T. Diehl, D. A. Goldstein, D. Gruen, T. S. Li, H. Lin, J. Marriner, J. J. Mohr, E. Neilsen, C.-C. Ngeow, K. Paech, E. S. Rykoff, M. Sako, I. Sevilla-Noarbe, E. Sheldon, F. Sobreira, D. L. Tucker, W. Wester
The Dark Energy Survey Image Processing Pipeline, E. Morganson, R. A. Gruendl, F. Menanteau, M. Carrasco Kind, Y.-C. Chen, G. Daues, A. Drlica-Wagner, D. N. Friedel, M. Gower, M. W. G. Johnson, M. D. Johnson, R. Kessler, F. Paz-Chinchón, D. Petravick, C. Pond, B. Yanny, S. Allam, R. Armstrong, Wayne A. Barkhouse, K. Bechtol, A. Benoit-Lévy, G. M. Bernstein, E. Bertin, E. Buckley-Geer, R. Covarrubias, S. Desai, H. T. Diehl, D. A. Goldstein, D. Gruen, T. S. Li, H. Lin, J. Marriner, J. J. Mohr, E. Neilsen, C.-C. Ngeow, K. Paech, E. S. Rykoff, M. Sako, I. Sevilla-Noarbe, E. Sheldon, F. Sobreira, D. L. Tucker, W. Wester
Physics Faculty Publications
The Dark Energy Survey (DES) is a five-year optical imaging campaign with the goal of understanding the origin of cosmic acceleration. DES performs a ~5000 deg2 survey of the southern sky in five optical bands (g, r, i, z, Y) to a depth of ~24th magnitude. Contemporaneously, DES performs a deep, time-domain survey in four optical bands (g, r, i, z) over ~27 deg2. DES exposures are processed nightly with an evolving data reduction pipeline and evaluated for image quality to determine if they need to be retaken. Difference imaging and transient source detection are also …
The Sluggs Survey: Dark Matter Fractions At Large Radii And Assembly Epochs Of Early-Type Galaxies From Globular Cluster Kinematics, Adebusola Alabi, Duncan Forbes, Aaron Romanowsky, Jean Brodie, Jay Strader, Joachim Janz, Christopher Usher, Lee Spitler, Sabine Bellstedt, Anna Ferré-Mateu
The Sluggs Survey: Dark Matter Fractions At Large Radii And Assembly Epochs Of Early-Type Galaxies From Globular Cluster Kinematics, Adebusola Alabi, Duncan Forbes, Aaron Romanowsky, Jean Brodie, Jay Strader, Joachim Janz, Christopher Usher, Lee Spitler, Sabine Bellstedt, Anna Ferré-Mateu
Faculty Publications
We use globular cluster kinematics data, primarily from the SAGES Legacy Unifying Globulars and GalaxieS (SLUGGS) survey, to measure the dark matter fraction (fDM) and the average dark matter density (〈ρDM〉) within the inner 5 effective radii (Re) for 32 nearby early-type galaxies (ETGs) with stellar mass log (M*/M⊙) ranging from 10.1 to 11.8. We compare our results with a simple galaxy model based on scaling relations as well as with cosmological hydrodynamical simulations where the dark matter profile has been modified through various physical processes. We find a high fDM (≥0.6) within 5 Re in most of our sample, …
Hecs-Sz: The Hectospec Survey Of Sunyaev-Zeldovich-Selected Clusters, Kenneth J. Rines, Margaret J. Geller, Antonaldo Diaferio, Ho Seong Hwang
Hecs-Sz: The Hectospec Survey Of Sunyaev-Zeldovich-Selected Clusters, Kenneth J. Rines, Margaret J. Geller, Antonaldo Diaferio, Ho Seong Hwang
Physics & Astronomy
We estimate cluster masses and velocity dispersions for 123 clusters from optical spectroscopy to compare the Sunyaev–Zeldovich (SZ) mass proxy and dynamical masses. Our new survey, HeCS-SZ (Hectospec Cluster Survey of SZ-selected clusters), includes 7721 new or remeasured redshifts from MMT/Hectospec observations of 21 SZ-selected clusters at redshifts z = 0.05–0.20. We supplement the Hectospec data with spectra from the Sloan Digital Sky Survey (SDSS) and cluster data from the Cluster Infall Regions in SDSS project and the Hectospec Cluster Survey, our Hectospec survey of clusters selected by X-ray flux. We measure the scaling relation between velocity dispersion and SZ …
Galaxy And Mass Assembly (Gama) : Panchromatic Data Release (Far-Uv–Far-Ir) And The Low-Z Energy Budget., Simon P. Driver, Angus H. Wright, Stephen K. Andrews, Luke J. M. Davies, Prajwal R. Kafle, Rebecca Lange, Amanda J. Moffett, Elizabeth Mannering, Aaron S. G. Robotham, Kevin Vinsen, Mehmet Alpaslan, Ellen Andrae, Ivan K. Baldry, Amanda E. Bauer, Steven P. Bamford, Joss Bland-Hawthorn, Nathan Bourne, Sarah Brough, Michael J. I. Brown, Michelle Cluver, Scott M. Croom, Matthew Colless, Christopher J. Conselice, Elisabete Da Cunha, Roberto De Propris, Michael Drinkwater, Loretta Dunne, Steve Eales, Alastair Edge, Carlos Frenk, Alister W. Graham, Meiert Grootes, Benne W. Holwerda, Andrew M. Hopkins, Edo Ibar, Eelco Van Kampen, Lee S. Kelvin, Tom Jarrett, D. Heath Jones, Maritza A. Lara-Lopez, Jochen Liske, Angel R. Lopez-Sanchez, Jon Loveday, Steve J. Maddox, Barry Madore, Smriti Mahajan, Martin Meyer, Peder Norberg, Samantha J. Penny, Steven Phillipps, Cristina C. Popescu, Richard Tuffs, John A. Peacock, Kevin A. Pimbblet, Matthew Prescott, Kate Rowlands, Anne E. Sansom, Mark Seibert, Matthew W. L. Smith, Will J. Sutherland, Edward N. Taylor, Elisabetta Valiante, J. Antonio Vazquez-Mata, Lingyu Wang, Stephen M. Wilkins, Richard P. Williams
Galaxy And Mass Assembly (Gama) : Panchromatic Data Release (Far-Uv–Far-Ir) And The Low-Z Energy Budget., Simon P. Driver, Angus H. Wright, Stephen K. Andrews, Luke J. M. Davies, Prajwal R. Kafle, Rebecca Lange, Amanda J. Moffett, Elizabeth Mannering, Aaron S. G. Robotham, Kevin Vinsen, Mehmet Alpaslan, Ellen Andrae, Ivan K. Baldry, Amanda E. Bauer, Steven P. Bamford, Joss Bland-Hawthorn, Nathan Bourne, Sarah Brough, Michael J. I. Brown, Michelle Cluver, Scott M. Croom, Matthew Colless, Christopher J. Conselice, Elisabete Da Cunha, Roberto De Propris, Michael Drinkwater, Loretta Dunne, Steve Eales, Alastair Edge, Carlos Frenk, Alister W. Graham, Meiert Grootes, Benne W. Holwerda, Andrew M. Hopkins, Edo Ibar, Eelco Van Kampen, Lee S. Kelvin, Tom Jarrett, D. Heath Jones, Maritza A. Lara-Lopez, Jochen Liske, Angel R. Lopez-Sanchez, Jon Loveday, Steve J. Maddox, Barry Madore, Smriti Mahajan, Martin Meyer, Peder Norberg, Samantha J. Penny, Steven Phillipps, Cristina C. Popescu, Richard Tuffs, John A. Peacock, Kevin A. Pimbblet, Matthew Prescott, Kate Rowlands, Anne E. Sansom, Mark Seibert, Matthew W. L. Smith, Will J. Sutherland, Edward N. Taylor, Elisabetta Valiante, J. Antonio Vazquez-Mata, Lingyu Wang, Stephen M. Wilkins, Richard P. Williams
Faculty Scholarship
We present the Galaxy And Mass Assembly (GAMA) Panchromatic Data Release (PDR) constituting over 230 deg2 of imaging with photometry in 21 bands extending from the far-UV to the far-IR. These data complement our spectroscopic campaign of over 300k galaxies, and are compiled from observations with a variety of facilities including: GALaxy Evolution eXplorer, Sloan Digital Sky Survey, Visible and Infrared Telescope for Astronomy (VISTA), Wide-field Infrared Survey Explorer, and Herschel, with the GAMA regions currently being surveyed by VLT Survey Telescope (VST) and scheduled for observations by Australian Square Kilometer Array Pathfinder (ASKAP). These data are processed to a …
Bright Galaxies At Hubble's Redshift Detection Frontier : Preliminary Results And Design From The Redshift Z ~ 9-10 Borg Pure-Parallel Hst Survey., V. Calvi, M. Trenti, M. Stiavelli, P. A. Oesch, L. Bradley, K. B. Schmidt, D. Coe, G. Brammer, S. Bernard, R. J. Bouwens, D. Carrasco, C. M. Carollo, Benne W. Holwerda, J. W. Mackenty, C. A. Mason, J. M. Shull, T. Treu
Bright Galaxies At Hubble's Redshift Detection Frontier : Preliminary Results And Design From The Redshift Z ~ 9-10 Borg Pure-Parallel Hst Survey., V. Calvi, M. Trenti, M. Stiavelli, P. A. Oesch, L. Bradley, K. B. Schmidt, D. Coe, G. Brammer, S. Bernard, R. J. Bouwens, D. Carrasco, C. M. Carollo, Benne W. Holwerda, J. W. Mackenty, C. A. Mason, J. M. Shull, T. Treu
Faculty Scholarship
We present the first results and design from the redshift z ∼ 9–10 Brightest of the Reionizing Galaxies Hubble Space Telescope survey BoRG[z9–10], aimed at searching for intrinsically luminous unlensed galaxies during the first 700 Myr after the Big Bang. BoRG[z9–10] is the continuation of a multi-year pure-parallel near-IR and optical imaging campaign with the Wide Field Camera 3. The ongoing survey uses five filters, optimized for detecting the most distant objects and offering continuous wavelength coverage from λ = 0.35 μm to λ = 1.7 μm. We analyze the initial ∼130 arcmin2 of area over 28 independent lines of …
Comparing Dense Galaxy Cluster Redshift Surveys With Weak-Lensing Maps, Ho Seong Hwang, Margaret J. Geller, Antonaldo Diaferio, Kenneth J. Rines, J. Jabran Zahid
Comparing Dense Galaxy Cluster Redshift Surveys With Weak-Lensing Maps, Ho Seong Hwang, Margaret J. Geller, Antonaldo Diaferio, Kenneth J. Rines, J. Jabran Zahid
Physics & Astronomy
We use dense redshift surveys of nine galaxy clusters at z ~ 0.2 to compare the galaxy distribution in each system with the projected matter distribution from weak lensing. By combining 2087 new MMT/Hectospec redshifts and the data in the literature, we construct spectroscopic samples within the region of weak-lensing maps of high (70%-89%) and uniform completeness. With these dense redshift surveys, we construct galaxy number density maps using several galaxy subsamples. The shape of the main cluster concentration in the weak-lensing maps is similar to the global morphology of the number density maps based on cluster members alone, mainly …
The Luminosity Function At Z ~ 8 From 97 Y-Band Dropouts : Inferences About Reionization., Kasper B. Schmidt, Tommaso Treu, Michele Trenti, Larry D. Bradley, Brandon C. Kelly, Pascal A. Oesch, Benne W. Holwerda, J. Michael Shull, Massimo Stiavelli
The Luminosity Function At Z ~ 8 From 97 Y-Band Dropouts : Inferences About Reionization., Kasper B. Schmidt, Tommaso Treu, Michele Trenti, Larry D. Bradley, Brandon C. Kelly, Pascal A. Oesch, Benne W. Holwerda, J. Michael Shull, Massimo Stiavelli
Faculty Scholarship
We present the largest search to date for Y-band dropout galaxies (z ∼ 8 Lyman break galaxies, LBGs) based on 350 arcmin2 of Hubble Space Telescope observations in the V, Y, J, and H bands from the Brightest of Reionizing Galaxies (BoRG) survey. In addition to previously published data, the BoRG13 data set presented here includes approximately 50 arcmin2 of new data and deeper observations of two previous BoRG pointings, from which we present 9 new z ∼ 8 LBG candidates, bringing the total number of BoRG Y-band dropouts to 38 with 25.5 mJ 27.6 (AB system). We introduce a …
The X-Ray Properties Of Optically Selected Clusters Of Galaxies, A. K. Hicks, G. W. Pratt, M. Donahue, E. Ellingson, M. Gladders, H. Böhringer, H. K. C. Yee, Renbin Yan, J. H. Croston, D. G. Gilbank
The X-Ray Properties Of Optically Selected Clusters Of Galaxies, A. K. Hicks, G. W. Pratt, M. Donahue, E. Ellingson, M. Gladders, H. Böhringer, H. K. C. Yee, Renbin Yan, J. H. Croston, D. G. Gilbank
Physics and Astronomy Faculty Publications
We present the results of Chandra and Suzaku X-ray observations of nine moderate-redshift (0.16 < z < 0.42) clusters discovered via the Red-sequence Cluster Survey (RCS). Surface brightness profiles are fitted to β-models, gas masses are determined, integrated spectra are extracted within R2500, and X-ray temperatures and luminosities are inferred. TheLX–TX relationship expected from self-similar evolution is tested by comparing this sample to our previous X-ray investigation of nine high-redshift (0.6 < z < 1.0) optically selected clusters. We find that optically selected clusters are systematically less luminous than X-ray selected clusters of similar X-ray temperature at both moderate and high z. We are unable to constrain evolution in the LX–TX relation with these data, but find it consistent with no evolution, within relatively large uncertainties. To investigate selection effects, we compare the X-ray properties of our sample to those of clusters in the …
Measuring The Ultimate Halo Mass Of Galaxy Clusters: Redshifts And Mass Profiles From The Hectospec Cluster Survey (Hecs), Kenneth J. Rines
Measuring The Ultimate Halo Mass Of Galaxy Clusters: Redshifts And Mass Profiles From The Hectospec Cluster Survey (Hecs), Kenneth J. Rines
Physics & Astronomy
The infall regions of galaxy clusters represent the largest gravitationally bound structures in a LambdaCDM universe. Measuring cluster mass profiles into the infall regions provides an estimate of the ultimate mass of these halos. We use the caustic technique to measure cluster mass profiles from galaxy redshifts obtained with the Hectospec Cluster Survey (HeCS), an extensive spectroscopic survey of galaxy clusters with MMT/Hectospec. We survey 58 clusters selected by X-ray flux at 0.1 < z < 0.3. The survey includes 22,680 unique MMT/Hectospec redshifts for individual galaxies; 10,145 of these galaxies are cluster members. For each cluster, we acquired high signal-to-noise spectra for ~200 cluster members and a comparable number of foreground/background galaxies. The cluster members trace out infall patterns around the clusters. The members define a very narrow red sequence. We demonstrate that the determination of velocity dispersion is insensitive to the inclusion of bluer members (a small fraction of the cluster population). We apply the caustic technique to define membership and estimate the mass profiles to large radii. The ultimate halo mass of clusters (the mass that remains bound in the far future of a LambdaCDM universe) is on average (1.99 ± 0.11)M 200, a new observational cosmological test in essential agreement with simulations. Summed profiles binned in M 200 and in LX demonstrate that the predicted Navarro-Frenk-White …
Measuring The Mass Distribution In Galaxy Clusters, Margaret J. Geller, Antonaldo Diaferio, Kenneth J. Rines, Ana Laura Serra
Measuring The Mass Distribution In Galaxy Clusters, Margaret J. Geller, Antonaldo Diaferio, Kenneth J. Rines, Ana Laura Serra
Physics & Astronomy
Cluster mass profiles are tests of models of structure formation. Only two current observational methods of determining the mass profile, gravitational lensing, and the caustic technique are independent of the assumption of dynamical equilibrium. Both techniques enable the determination of the extended mass profile at radii beyond the virial radius. For 19 clusters, we compare the mass profile based on the caustic technique with weak lensing measurements taken from the literature. This comparison offers a test of systematic issues in both techniques. Around the virial radius, the two methods of mass estimation agree to within ~30%, consistent with the expected …
The Brightest Of Reionizing Galaxies Survey : Constraints On The Bright End Of The Z ~ 8 Luminosity Function., L. D. Bradley, M. Trenti, P. A. Oesch, M. Stiavelli, T. Treu, R. J. Bouwens, J. M. Shull, Benne W. Holwerda, N. Pirzkal
The Brightest Of Reionizing Galaxies Survey : Constraints On The Bright End Of The Z ~ 8 Luminosity Function., L. D. Bradley, M. Trenti, P. A. Oesch, M. Stiavelli, T. Treu, R. J. Bouwens, J. M. Shull, Benne W. Holwerda, N. Pirzkal
Faculty Scholarship
We report the discovery of 33 Lyman-break galaxy candidates at z ∼ 8 detected in Hubble Space Telescope Wide Field Camera 3 (WFC3) imaging as part of the Brightest of Reionizing Galaxies (BoRG) pure-parallel survey. The ongoing BoRG survey currently has the largest area (274 arcmin2) with Y098 (or Y105), J125, and H160 band coverage needed to search for z ∼ 8 galaxies, about three times the current CANDELS area, and slightly larger than what will be the final CANDELS wide component with Y105 data (required to select z ∼ 8 sources). Our sample of 33 relatively bright Y098-dropout galaxies …
The Vlt Lbg Redshift Survey I: Clustering And Dynamics Of ≈ 1000 Galaxies At Z ≈ 3⋆, R. M. Bielby, T. Shanks, P. M. Weilbacher, L. Infante, N. H.M. Crighton, C. Bornancini, N. Bouché, P. Héraudeau, D. G. Lambas, James D. Lowenthal, D. Minniti, N. Padilla, P. Petitjean, T. Theuns
The Vlt Lbg Redshift Survey I: Clustering And Dynamics Of ≈ 1000 Galaxies At Z ≈ 3⋆, R. M. Bielby, T. Shanks, P. M. Weilbacher, L. Infante, N. H.M. Crighton, C. Bornancini, N. Bouché, P. Héraudeau, D. G. Lambas, James D. Lowenthal, D. Minniti, N. Padilla, P. Petitjean, T. Theuns
Astronomy: Faculty Publications
We present the initial imaging and spectroscopic data acquired as part of the Very Large Telescope (VLT) VIMOS Lyman-break galaxy Survey. UBR (or UBVI) imaging covers five ≈36 × 36 arcmin fields centred on bright z > 3 quasi-stellar objects (QSOs), allowing ≈210002 < z < 3.5 galaxy candidates to be selected using the Lyman-break technique. We performed spectroscopic follow-up using VLT VIMOS, measuring redshifts for 1020 z > 2 Lyman-break galaxies and 10 z > 2 QSOs from a total of 19 VIMOS pointings. From the galaxy spectra, we observe a 625 ± 510kms velocity offset between the interstellar absorption and Lyman α emission-line redshifts, consistent with previous results. Using the photometric and spectroscopic catalogues, we have analysed the galaxy clustering at z≈ 3. The angular correlation …
Scaling Relations And Overabundance Of Massive Clusters At Z ≳ 1 From Weak-Lensing Studies With The Hubble Space Telescope, M J. Jee, Ks Dawson, H Hoekstra, S Perlmutter, P Rosati, M Brodwin, N Sukuzi, B Koester, M Postman, L Lubin, J Meyers, Sa Stanford, K Barbary, F Barrientos, P Eisenhardt, Hc Ford, Dg Gibank, Md Gladders, A Gonzalez, Dw Harris, Xiaosheng Huang, C Lidman, Es Rykoff, D Rubin, Al Spadafora
Scaling Relations And Overabundance Of Massive Clusters At Z ≳ 1 From Weak-Lensing Studies With The Hubble Space Telescope, M J. Jee, Ks Dawson, H Hoekstra, S Perlmutter, P Rosati, M Brodwin, N Sukuzi, B Koester, M Postman, L Lubin, J Meyers, Sa Stanford, K Barbary, F Barrientos, P Eisenhardt, Hc Ford, Dg Gibank, Md Gladders, A Gonzalez, Dw Harris, Xiaosheng Huang, C Lidman, Es Rykoff, D Rubin, Al Spadafora
Physics and Astronomy
We present weak gravitational lensing analysis of 22 high-redshift (z 1) clusters based on Hubble Space Telescope images. Most clusters in our sample provide significant lensing signals and are well detected in their reconstructed two-dimensional mass maps. Combining the current results and our previous weak-lensing studies of five other high-z clusters, we compare gravitational lensing masses of these clusters with other observables. We revisit the question whether the presence of the most massive clusters in our sample is in tension with the current ΛCDM structure formation paradigm. We find that the lensing masses are tightly correlated with the …
The Dearth Of Chemically Enriched Warm-Hot Circumgalactic Gas, Y Yao, Qd Wang, Sv Penton, Tm Tripp, Jm Shull, Jt Stocke
The Dearth Of Chemically Enriched Warm-Hot Circumgalactic Gas, Y Yao, Qd Wang, Sv Penton, Tm Tripp, Jm Shull, Jt Stocke
Astronomy Department Faculty Publication Series
The circumgalactic medium (CGM) around galaxies is believed to record various forms of galaxy feedback and contain a significant portion of the "missing baryons" of individual dark matter halos. However, clear observational evidence for the existence of the hot CGM is still absent. We use intervening galaxies along 12 background active galactic nuclei (AGNs) as tracers to search for X-ray absorption lines produced in the corresponding CGM. Stacking Chandra grating observations with respect to galaxy groups and different luminosities of these intervening galaxies, we obtain spectra with signal-to-noise ratios of 46-72 per 20 mÅ spectral bin at the expected O …
Dynamics Of Lyman Break Galaxies And Their Host Halos, James D. Lowenthal, David C. Koo, Luc Simard, Eelco Van Kampen
Dynamics Of Lyman Break Galaxies And Their Host Halos, James D. Lowenthal, David C. Koo, Luc Simard, Eelco Van Kampen
Astronomy: Faculty Publications
We present deep two-dimensional spectra of 22 candidate and confirmed Lyman break galaxies (LBGs) at redshifts 2 < z < 4 in the Hubble Deep Field (HDF) obtained at the Keck II telescope. The targets were preferentially selected with spatial extent and/or multiple knot morphologies, and we used slitmasks and individual slits tilted to optimize measurement of any spatially resolved kinematics. Our sample is more than 1 mag fainter and is at higher redshift than the kinematic LBG targets previously studied by others. The median target magnitude was I814 = 25.3, and total exposure times ranged from 10 to 50 ks. We measure redshifts, some new, ranging from z = 0.2072 to z = 4.056, including two interlopers at z < 1, and resulting in a sample of 14 LBGs with a median redshift z = 2.424. The morphologies and kinematics of the close pairs and multiple knot sources in our sample are generally inconsistent with galaxy formation scenarios postulating that LBGs occur only at the bottom of the potential wells of massive host halos; rather, they support "collisional starburst" models with significant …
Large Area Survey For Z=7 Galaxies In Sdf And Goods-N: Implications For Galaxy Formation And Cosmic Reionization, M Ouchi, B Mobasher, K Shimasaku, Hc Ferguson, Sm Fall, Y Ono, N Kashikawa, T Morokuma, K Nakajima, S Okamura, M Dickinson, M Giavalisco, K Ohta
Large Area Survey For Z=7 Galaxies In Sdf And Goods-N: Implications For Galaxy Formation And Cosmic Reionization, M Ouchi, B Mobasher, K Shimasaku, Hc Ferguson, Sm Fall, Y Ono, N Kashikawa, T Morokuma, K Nakajima, S Okamura, M Dickinson, M Giavalisco, K Ohta
Astronomy Department Faculty Publication Series
We present results of our large area survey for z'-band dropout galaxies at z = 7 in a 1568 arcmin2 sky area covering the SDF and GOODS-N fields. Combining our ultra-deep Subaru/Suprime-Cam z'- and y-band (λeff = 1 μm) images with legacy data of Subaru and Hubble Space Telescope, we have identified 22 bright z-dropout galaxies down to y = 26, one of which has a spectroscopic redshift of z = 6.96 determined from Lyα emission. The z = 7 luminosity function yields the best-fit Schechter parameters of ϕ* = 0.69+2.62−0.55 × 10−3 Mpc−3, …
Hubble Space Telescope/Advanced Camera For Surveys Morphology Of Ly Alpha Emitters At Redshift 5.7 In The Cosmos Field, Y Taniguchi, Et. Al.
Hubble Space Telescope/Advanced Camera For Surveys Morphology Of Ly Alpha Emitters At Redshift 5.7 In The Cosmos Field, Y Taniguchi, Et. Al.
Astronomy Department Faculty Publication Series
We present detailed morphological properties of Lyα emitters (LAEs) at z ≈ 5.7 in the COSMOS field based on Hubble Space Telescope Advanced Camera for Surveys (ACS) data. The ACS imaging in the F814W filter covered 85 LAEs of the 119 LAEs identified in the full two square degree field, and 47 LAEs of them are detected in the ACS images. Nearly half of them are spatially extended with a size larger than 0.15 arcsec (∼0.88 kpc at z = 5.7) and up to 0.4 arcsec (∼2.5 kpc at z = 5.7). The others are nearly unresolved compact objects. Two …
Two Bright Submillimeter Galaxies In A Z=4.05 Protocluster In Goods-North, And Accurate Radio-Infrared Photometric Redshifts, E Daddi, H Dannerbauer, D Stern, M Dickinson, G Morrison, D Elbaz, M Giavalisco, C Mancini, A Pope, H Spinrad
Two Bright Submillimeter Galaxies In A Z=4.05 Protocluster In Goods-North, And Accurate Radio-Infrared Photometric Redshifts, E Daddi, H Dannerbauer, D Stern, M Dickinson, G Morrison, D Elbaz, M Giavalisco, C Mancini, A Pope, H Spinrad
Astronomy Department Faculty Publication Series
No abstract provided.
An Intensive Hst Survey For Z>1 Supernovae By Targeting Galaxy Clusters, K S. Dawson, G Aldering, R Amanullah, K Barbary, L F. Barrientos, M Brodwin, N Connolly, A Dey, M Doi, M Donahue, P Eisenhardt, E Ellingson, L Faccioli, V Fadeyev, H K. Fakhouri, A S. Fruchter, D G. Gilbank, M D. Gladders, G Goldhaber, A H. Gonzalez, A Goobar, A Gude, T Hattori, H Hoekstra, Xiaosheng Huang, Y Ihara, B T. Jannuzi, D Johnston, K Kashikawa, B Koester, K Konishi, M Kowalski, C Lidman, E V. Linder, L Lubin, J Meyers, T Morokuma, F Munshi, C Mullis, T Oda, N Panagia, S Perlmutter, M Postman, T Pritchard, J Rhodes, P Rosati, D Rubin, D J. Schlegel, A Spadafora, S A. Stanford, V Stanishev, D Stern, M Strovink, N Suzuki, N Takanashi, K Tokita, M Wagner, L Wang, N Yasuda, H. K. C. Yee, Supernova Cosmology Project
An Intensive Hst Survey For Z>1 Supernovae By Targeting Galaxy Clusters, K S. Dawson, G Aldering, R Amanullah, K Barbary, L F. Barrientos, M Brodwin, N Connolly, A Dey, M Doi, M Donahue, P Eisenhardt, E Ellingson, L Faccioli, V Fadeyev, H K. Fakhouri, A S. Fruchter, D G. Gilbank, M D. Gladders, G Goldhaber, A H. Gonzalez, A Goobar, A Gude, T Hattori, H Hoekstra, Xiaosheng Huang, Y Ihara, B T. Jannuzi, D Johnston, K Kashikawa, B Koester, K Konishi, M Kowalski, C Lidman, E V. Linder, L Lubin, J Meyers, T Morokuma, F Munshi, C Mullis, T Oda, N Panagia, S Perlmutter, M Postman, T Pritchard, J Rhodes, P Rosati, D Rubin, D J. Schlegel, A Spadafora, S A. Stanford, V Stanishev, D Stern, M Strovink, N Suzuki, N Takanashi, K Tokita, M Wagner, L Wang, N Yasuda, H. K. C. Yee, Supernova Cosmology Project
Physics and Astronomy
We present a new survey strategy to discover and study high redshift Type Ia supernovae (SNe Ia) using the Hubble Space Telescope (HST). By targeting massive galaxy clusters at 0.9<zHST field survey and a factor of three improvement in the total yield of SN detections in relatively dust-free red-sequence galaxies. In total, sixteen SNe were discovered at z>0.95, nine of which were in galaxy clusters. This strategy provides a SN sample that can be used to decouple the effects of host galaxy extinction and intrinsic color in high redshift SNe, thereby reducing one of the …
X-Raying The Intergalactic O Vi Absorbers, Y Yao, Tm Tripp, Qd Wang, Cw Danforth, Cr Canizares, Jm Shull, Hl Marshall, L Song
X-Raying The Intergalactic O Vi Absorbers, Y Yao, Tm Tripp, Qd Wang, Cw Danforth, Cr Canizares, Jm Shull, Hl Marshall, L Song
Astronomy Department Faculty Publication Series
The observed intergalactic O VI absorbers at z>0 have been regarded as a significant reservoir of the "missing baryons." However, to fully understand how these absorbers contribute to the baryon inventory, it is crucial to determine whether the systems are collisionally ionized or photoionized (or both). Using the identified intergalactic O VI absorbers as tracers, we search for the corresponding X-ray absorption lines, which are useful for finding the missing baryons and for revealing the nature of the O VI absorbers. Stacking the Chandra grating spectra along six AGN sight lines, we obtain three spectra with signal-to-noise ratios of …
The Aztec/Sma Interferometric Imaging Survey Of Submillimeter-Selected High-Redshift Galaxies, Jd Younger, Gg Fazio, Js Huang, Min Yun, Gw Wilson, Mln Ashby, Ma Gurwell, Ab Peck, Gr Petitpas, Dj Wilner, Dh Hughes, I Aretxaga, S Kim, Ks Scott, J Austermann, T Perera, Jd Lowenthal
The Aztec/Sma Interferometric Imaging Survey Of Submillimeter-Selected High-Redshift Galaxies, Jd Younger, Gg Fazio, Js Huang, Min Yun, Gw Wilson, Mln Ashby, Ma Gurwell, Ab Peck, Gr Petitpas, Dj Wilner, Dh Hughes, I Aretxaga, S Kim, Ks Scott, J Austermann, T Perera, Jd Lowenthal
Astronomy Department Faculty Publication Series
We present results from a continuing interferometric survey of high-redshift submillimeter galaxies (SMGs) with the Submillimeter Array, including high-resolution (beam size ~2 arcsec) imaging of eight additional AzTEC 1.1 mm selected sources in the COSMOS field, for which we obtain six reliable (peak signal-to-noise ratio (S/N) >5 or peak S/N >4 with multiwavelength counterparts within the beam) and two moderate significance (peak S/N >4) detections. When combined with previous detections, this yields an unbiased sample of millimeter-selected SMGs with complete interferometric follow up. With this sample in hand, we (1) empirically confirm the radio-submillimeter association, (2) examine the submillimeter morphology—including …
The Aztec/Sma Interferometric Imaging Survey Of Submillimeter-Selected High-Redshift Galaxies, Joshua D. Younger, Giovanni G. Fazio, Jia Sheng Huang, Min S. Yun, Grant W. Wilson, Matthew L.N. Ashby, Mark A. Gurwell, Alison B. Peck, Glen R. Petitpas, David J. Wilner, David H. Hughes, Itziar Aretxaga, Sungeun Kim, Kimberly S. Scott, Jason Austermann, Thushara Perera, James D. Lowenthal
The Aztec/Sma Interferometric Imaging Survey Of Submillimeter-Selected High-Redshift Galaxies, Joshua D. Younger, Giovanni G. Fazio, Jia Sheng Huang, Min S. Yun, Grant W. Wilson, Matthew L.N. Ashby, Mark A. Gurwell, Alison B. Peck, Glen R. Petitpas, David J. Wilner, David H. Hughes, Itziar Aretxaga, Sungeun Kim, Kimberly S. Scott, Jason Austermann, Thushara Perera, James D. Lowenthal
Astronomy: Faculty Publications
We present results from a continuing interferometric survey of high-redshift submillimeter galaxies (SMGs) with the Submillimeter Array, including high-resolution (beam size ∼ 2 arcsec) imaging of eight additional AzTEC 1.1 mm selected sources in the COSMOS field, for which we obtain six reliable (peak signal-to-noise ratio (S/N) >5 or peak S/N >4 with multiwavelength counterparts within the beam) and two moderate significance (peak S/N >4) detections. When combined with previous detections, this yields an unbiased sample of millimeter-selected SMGs with complete interferometric follow up. With this sample in hand, we (1) empirically confirm the radio-submillimeter association, (2) examine the submillimeter …
The Chandra Cosmos Survey. I. Overview And Point Source Catalog, M Elvis, F Civano, C Vignali, S Puccetti, F Fiore, N Cappelluti, Tl Aldcroft, A Fruscione, G Zamorani, A Comastri, M Brusa, R Gilli, T Miyaji, F Damiani, Am Koekemoer, A Finoguenov, H Brunner, Cm Urry, J Silverman, V Mainieri, G Hasinger, R Griffiths, M Carollo, H Hao, L Guzzo, A Blain, D Calzetti, C Carilli, P Capak, S Ettori, G Fabbiano, C Impey, S Lilly, B Mobasher, M Rich, M Salvato, Db Sanders, E Schinnerer, N Scoville, P Shopbell, Je Taylor, Y Taniguchi, M Volonteri
The Chandra Cosmos Survey. I. Overview And Point Source Catalog, M Elvis, F Civano, C Vignali, S Puccetti, F Fiore, N Cappelluti, Tl Aldcroft, A Fruscione, G Zamorani, A Comastri, M Brusa, R Gilli, T Miyaji, F Damiani, Am Koekemoer, A Finoguenov, H Brunner, Cm Urry, J Silverman, V Mainieri, G Hasinger, R Griffiths, M Carollo, H Hao, L Guzzo, A Blain, D Calzetti, C Carilli, P Capak, S Ettori, G Fabbiano, C Impey, S Lilly, B Mobasher, M Rich, M Salvato, Db Sanders, E Schinnerer, N Scoville, P Shopbell, Je Taylor, Y Taniguchi, M Volonteri
Astronomy Department Faculty Publication Series
The Chandra COSMOS Survey (C-COSMOS) is a large, 1.8 Ms, Chandra program that has imaged the central 0.5 deg2 of the COSMOS field (centered at 10 h , +02 o ) with an effective exposure of ~160 ks, and an outer 0.4 deg2 area with an effective exposure of ~80 ks. The limiting source detection depths are 1.9 × 10–16 erg cm–2 s–1 in the soft (0.5-2 keV) band, 7.3 × 10–16 erg cm–2 s–1 in the hard (2-10 keV) band, and 5.7 × 10–16 erg cm–2 s–1 in the full (0.5-10 keV) band. Here we describe the strategy, design, …
Spectroscopic Observations Of Lyman Break Galaxies At Redshifts Similar To 4, 5, And 6 In The Goods-South Field, E Vanzella, M Giavalisco, M Dickinson, S Cristiani, M Nonino, H Kuntschner, P Popesso, P Rosati, A Renzini, D Stern, C Cesarsky, Hc Ferguson, Rae Fosbury
Spectroscopic Observations Of Lyman Break Galaxies At Redshifts Similar To 4, 5, And 6 In The Goods-South Field, E Vanzella, M Giavalisco, M Dickinson, S Cristiani, M Nonino, H Kuntschner, P Popesso, P Rosati, A Renzini, D Stern, C Cesarsky, Hc Ferguson, Rae Fosbury
Astronomy Department Faculty Publication Series
We report on observations of Lyman-break galaxies (LBGs) selected from the Great Observatories Origins Deep Survey at mean redshift z~4, 5 and 6, obtained with FORS2 spectrograph at the ESO-VLT.This program has yielded spectroscopic identifications for 114 galaxies of which 51 are at z~4, 31 at z~5, and 32 at z~6. The adopted selection criteria are effective, identifying galaxies at the expected redshift with minimal foreground contamination. Once selection effects are properly accounted for, the rest-frame UV spectra of the higher-redshift LBGs appear to be similar to their counterparts at z~3. As at z~3, LBGs at z~4 and z~5 show …
SPitzer Irac Infrared Colours Of Submillimetre-Bright Galaxies, Min S. Yun, Itziar Aretxaga, Matthew L.N. Ashby, Jason Austermann, Giovanni G. Fazio, Mauro Giavalisco, Jia Sheng Huang, David H. Hughes, Sungeun Kim, James D. Lowenthal, Thushara Perera, Kim Scott, Grant Wilson, Joshua D. Younger
SPitzer Irac Infrared Colours Of Submillimetre-Bright Galaxies, Min S. Yun, Itziar Aretxaga, Matthew L.N. Ashby, Jason Austermann, Giovanni G. Fazio, Mauro Giavalisco, Jia Sheng Huang, David H. Hughes, Sungeun Kim, James D. Lowenthal, Thushara Perera, Kim Scott, Grant Wilson, Joshua D. Younger
Astronomy: Faculty Publications
High-redshift submillimetre-bright galaxies identified by blank field surveys at millimetre and submillimetre wavelengths appear in the region of the Infra Red Array Camera (IRAC) colour-colour diagrams previously identified as the domain of luminous active galactic nuclei (AGNs). Our analysis using a set of empirical and theoretical dusty starburst spectral energy distribution (SED) models shows that power-law continuum sources associated with hot dust heated by young (≲100 Myr old), extreme starbursts at z > 2 also occupy the same general area as AGNs in the IRAC colour-colour plots. A detailed comparison of the IRAC colours and SEDs demonstrates that the two populations …
Host Galaxy Extinction Of Type Ia Supernovae : Co-Evolution Of Interstellar Medium Structure And The Extinction Law With Star Formation., Benne W. Holwerda
Host Galaxy Extinction Of Type Ia Supernovae : Co-Evolution Of Interstellar Medium Structure And The Extinction Law With Star Formation., Benne W. Holwerda
Faculty Scholarship
This paper presents a mechanism that may modify the extinction law for Type Ia supernovae (SNeIa) observed at higher redshift. Starting from the observations that (i) SNeIa occur predominantly in spiral galaxies, (ii) star formation ejects interstellar medium (ISM) out of the plane of spirals, (iii) star formation alters the extinction properties of the dust in the ISM, and (iv) there is substantially more star formation at higher redshift, I propose that spiral galaxies have a dustier halo in the past than they do now. The ejected material’s lower value of RV will lead to a lower average value (R¯ …
Spitzer Irac Infrared Colours Of Submillimetre-Bright Galaxies, Min Yun, I Aretxaga, Mln Ashby, J Austermann, Gg Fazio, M Giavalisco, Js Huang, Dh Hughes, S Kim, Jd Lowenthal, T Perera, K Scott, G Wilson, Jd Younger
Spitzer Irac Infrared Colours Of Submillimetre-Bright Galaxies, Min Yun, I Aretxaga, Mln Ashby, J Austermann, Gg Fazio, M Giavalisco, Js Huang, Dh Hughes, S Kim, Jd Lowenthal, T Perera, K Scott, G Wilson, Jd Younger
Astronomy Department Faculty Publication Series
High-redshift submillimetre-bright galaxies identified by blank field surveys at millimetre and submillimetre wavelengths appear in the region of the Infra Red Array Camera (IRAC) colour–colour diagrams previously identified as the domain of luminous active galactic nuclei (AGNs). Our analysis using a set of empirical and theoretical dusty starburst spectral energy distribution (SED) models shows that power-law continuum sources associated with hot dust heated by young (≲100 Myr old), extreme starbursts at z > 2 also occupy the same general area as AGNs in the IRAC colour–colour plots. A detailed comparison of the IRAC colours and SEDs demonstrates that the two populations …