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Sep 22, 2013
09/13
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Paul Martini; Donald P. Schneider
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eye 42
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We present a new method to measure the episodic lifetime of quasars with current and future large-scale sky surveys. Future photometric observations of large samples of confirmed quasars can provide a direct measurement (or interesting lower limit) to the lifetime of an individual episode of quasar activity (t_Q) and potentially enable the study of post-quasar host galaxies. Photometric observations of the quasars found by the Sloan Digital Sky Survey (SDSS) and 2dF Survey could, with a time...
Source: http://arxiv.org/abs/astro-ph/0309650v1
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Sep 21, 2013
09/13
by
Naoki Yasuda; Masataka Fukugita; Donald P. Schneider
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Galactic extinction is tested using galaxy number counts at low Galactic latitude obtained from five band photometry of the Sloan Digital Sky Survey. The spatial variation of galaxy number counts for low extinction regions of $E(B-V) < 0.15$ is consistent with the all-sky reddening map of Schlegel, Finkbeiner, & Davis (1998) and the standard extinction law. For higher extinction regions of $E(B-V) > 0.15$, however, the map of Schlegel et al.(1998) overestimates the reddening by a...
Source: http://arxiv.org/abs/0706.0369v1
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48
Sep 22, 2013
09/13
by
John N. Bahcall; Sofia Kirhakos; Donald P. Schneider
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eye 48
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Strong upper limits are placed on the visual-band brightnesses of galactic hosts for four luminous, radio-quiet quasars with redshifts between $0.16$ and~$0.24$ that were studied with the HST's Wide Field/Planetary Camera-2. Typical upper limits on the luminosities of galactic hosts are about $1.4$ mag fainter than $L^*$ for spirals and about $0.5$ mag fainter than $L^*$ for ellipticals. The galactic hosts of the quasars are more than a magnitude and a half fainter than the median integrated...
Source: http://arxiv.org/abs/astro-ph/9409028v1
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Sep 22, 2013
09/13
by
Shai Kaspi; W. N. Brandt; Donald P. Schneider
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eye 47
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We report on a search for X-ray emission from quasars with redshifts greater than four using the ROSAT public database. Our search has doubled the number of z>4 quasars detected in X-rays from 6 to 12. Most of those known prior to this work were radio-loud and X-ray selected sources; our study increases the number of X-ray detected, optically selected z>4 quasars from one to seven. We present their basic X-ray properties and compare these to those of lower redshift quasars. We do not find...
Source: http://arxiv.org/abs/astro-ph/0001299v1
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Sep 19, 2013
09/13
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John N. Bahcall; Sofia Kirhakos; Donald P. Schneider
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HST observations of eight intrinsically luminous quasars with redshifts between $0.16$ and~$0.29$ are presented. Seven companion galaxies brighter than $M_V = -16.5$ lie within a projected distance of 25 kpc of the quasars; three of the companions are located closer than $3''$ (6 kpc projected distance) from the quasars, well within the volume that would be enclosed by a typical $L^*$ host galaxy. The observed association of quasars and companion galaxies is statistically significant and may be...
Source: http://arxiv.org/abs/astro-ph/9501018v1
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Sep 18, 2013
09/13
by
John N. Bahcall; Sofia Kirhakos; Donald P. Schneider
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HST images (with WFPC2) of PHL~909\ ($z = 0.171$) and PG~0052$+$251\ ($z = 0.155$) show that these luminous radio-quiet quasars each occur in an apparently normal host galaxy. The host galaxy of PHL~909 is an elliptical galaxy ($\sim$ E4) and the host of PG~0052$+$251 is a spiral ($\sim$~Sb). Both host galaxies are several tenths of a magnitude brighter than $L^*$, the characteristic Schechter luminosity of field galaxies. The images of PHL~909 and PG~0052$+$251, when compared with HST images...
Source: http://arxiv.org/abs/astro-ph/9509031v1
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Sep 19, 2013
09/13
by
Stephen R. Kane; Donald P. Schneider; Jian Ge
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Radial velocity surveys for extra-solar planets generally require substantial amounts of large telescope time in order to monitor a sufficient number of stars. Two of the aspects which can limit such surveys are the single-object capabilities of the spectrograph, and an inefficient observing strategy for a given observing window. In addition, the detection rate of extra-solar planets using the radial velocity method has thus far been relatively linear with time. With the development of various...
Source: http://arxiv.org/abs/astro-ph/0703344v1
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Sep 21, 2013
09/13
by
Robert R. Gibson; W. N. Brandt; Donald P. Schneider
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We analyze archived Chandra and XMM-Newton X-ray observations of 536 Sloan Digital Sky Survey (SDSS) Data Release 5 (DR5) quasars (QSOs) at 1.7
Source: http://arxiv.org/abs/0808.2603v1
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Sep 23, 2013
09/13
by
Osamu Nakamura; Masataka Fukugita; Jon Brinkmann; Donald P. Schneider
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eye 63
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We present a study of the H$\alpha$ line emission from a sample of 1482 optically-selected, morphologically-classified bright galaxies (median redshift of 0.05) derived from the Sloan Digital Sky Survey. The luminosity function is calculated for each morphological class and for the total sample. The luminosity function fitted with the Schechter form gives a slope $\alpha=-1.43\pm 0.10$ for the total sample and the H$\alpha$ luminosity density is $10^{39.31\pm 0.04{+0.10\atop-0.07}}h$ erg...
Source: http://arxiv.org/abs/astro-ph/0312519v1
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44
Sep 23, 2013
09/13
by
Takamitsu Miyaji; Guenther Hasinger; Ingo Lehmann; Donald P. Schneider
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We report the results of our Chandra observations of six QSOs at $z\sim 3$ from the Palomer Transit Grism Survey. Our primary goal is to investigate the possible systematic change of $\alpha_{ox}$ between $z>4$ and $z\sim 3$, between which a rapid rise of luminous QSO number density with cosmic time is observed. The summed spectrum showed a power-law spectrum with photon index of $\Gamma \approx 1.9$, which is similar to other unabsorbed AGNs. Combining our $z\sim 3$ QSOs with X-ray...
Source: http://arxiv.org/abs/astro-ph/0510257v2
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Sep 19, 2013
09/13
by
William H. Press; George B. Rybicki; Donald P. Schneider
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Techniques for the statistical analysis of the \Lya\ forest in high redshift quasars are developed, and applied to the low resolution (25 \AA) spectra of 29 of the 33 quasars in the Schneider-Schmidt-Gunn (SSG) sample.We find that the mean absorption increases with $z$ approximately as a power law $(1+z)^{\gamma+1}$ with $\gamma = 2.46\pm 0.37$. The mean ratio of \Lya\ to Lyman $\beta$ absorption in the clouds is $0.476\pm 0.054$. We also detect, and obtain ratios, for Lyman $\beta$, $\gamma$,...
Source: http://arxiv.org/abs/astro-ph/9303016v1
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Jun 27, 2018
06/18
by
Shadab Alam; Shirley Ho; Mariana Vargas-Magaña; Donald P. Schneider
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The measured redshift ($z$) of an astronomical object is a combination of Hubble recession, gravitational redshift and peculiar velocity. The line of sight distance to a galaxy inferred from redshift is affected by the peculiar velocity component of galaxy redshift, which is observed as an anisotropy in the correlation function. This anisotropy allows us to measure the linear growth rate of matter ($f\sigma_8$). We measure the $f\sigma_8$ at $z=0.57$ using the CMASS sample from Data Release 11...
Topics: Astrophysics, Cosmology and Nongalactic Astrophysics
Source: http://arxiv.org/abs/1504.02100
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107
Jul 20, 2013
07/13
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Sofia Kirhakos; John N. Bahcall; Donald P. Schneider; Jerome Kristian
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eye 107
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Observations with the Wide-Field/Planetary Camera-2 of the Hubble Space Telescope (HST) are presented for three radio-loud quasars: 3C 48 (z=0.367), B2 1425+267 (z=0.366), and 3C 345 (z=0.594). All three quasars have luminous (~4 L^*) galaxies as hosts, which are either elliptical (B2 1425+267 and 3C 345) or interacting (3C 48), and all hosts are 0.5 - 1.0 mag bluer in (V-I) than other galaxies with the same overall morphology at similar redshifts to the quasars. The host of 3C 48 has many H II...
Source: http://arxiv.org/abs/astro-ph/9902175v1
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49
Sep 23, 2013
09/13
by
Puragra Guhathakurta; Brian Yanny; Donald P. Schneider; John N. Bahcall
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We describe images of the center of the dense globular cluster M15 (NGC 7078) obtained with the Hubble Space Telescope Wide Field and Planetary Camera 2 (WFPC2). Data taken in the F336W, F439W, and F555W filters (approximately U, B, and V) are used to study the surface density distribution of the $\sim3\times10^4$~stars detected in a 5~arcmin$^2$ region within $r
Source: http://arxiv.org/abs/astro-ph/9512015v1
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Sep 22, 2013
09/13
by
Stefano Zibetti; Simon D. M. White; Donald P. Schneider; Jon Brinkmann
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We analyse the spatial distribution and colour of the intracluster light (ICL) in 683 clusters of galaxies between z=0.2 and 0.3, selected from approx 1500 deg^2 of the SDSS-DR1. Surface photometry in the g, r and i bands is conducted on stacked images of the clusters, after rescaling them to the same metric size and masking out resolved sources. We are able to trace the average surface brightness profile of the ICL out to 700 kpc, where it is less than 1/10,000 of the mean surface brightness...
Source: http://arxiv.org/abs/astro-ph/0501194v1
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55
Sep 22, 2013
09/13
by
Amy E. Kimball; Željko Ivezić; Paul J. Wiita; Donald P. Schneider
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eye 55
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(Abridged) With the largest homogeneous quasar sample with optical spectra and robust radio morphology classifications assembled to date, we investigate quasar radio and optical properties with unprecedented statistical power. The data consist of 4714 radio quasars from FIRST with S_{20}>2mJy and SDSS spectra. Radio morphology classes include core-only (core), core-lobe (lobe), core-jet (jet), lobe-core-lobe (triple), and double-lobe. We examine the optical colors of radio-morphology...
Source: http://arxiv.org/abs/1103.4791v1
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165
Jul 20, 2013
07/13
by
Christopher W. Churchill; Donald P. Schneider; Maarten Schmidt; James E. Gunn
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The z=4.591 quasar PC 1415+3408 exhibits very strong associated metal-line absorption from the N V (1238,1242), Si IV (1393,1402), and C IV (1548,1550) doublets spanning the velocity interval -1700 < v < 0 km/s. Also present, are detached absorption troughs in N V and C IV spanning -5000 < v < -3000 km/s; this is characteristic of broad absorption line (BAL) quasars, but the small overall velocity spread suggests that PC 1415+3408 be classified as a Mini-BAL quasar. The N V doublet...
Source: http://arxiv.org/abs/astro-ph/9902371v1
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Sep 23, 2013
09/13
by
Masataka Fukugita; Osamu Nakamura; Donald P. Schneider; Mamoru Doi; Nobunari Kashikawa
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eye 59
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We present an investigation of the environment (\approx 600 kpc radius) of a pair of luminous z=4.25 quasars, SDSS J1439-0034 A,B, separated by 33''. An analysis of high-quality Subaru spectra of the quasars suggests that this configuration is indeed a physical pair and not a gravitational lens; the redshifts are slightly different (although marginally consistent with being the same), and the two spectra have strikingly different features. We search for bright galaxies (L\gsim 0.4 L^*) having...
Source: http://arxiv.org/abs/astro-ph/0312521v1
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56
Sep 22, 2013
09/13
by
Karl B. Fisher; John N. Bahcall; Sofia Kirhakos; Donald P. Schneider
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eye 56
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We examine the clustering of galaxies around a sample of 20 luminous low redshift (z
Source: http://arxiv.org/abs/astro-ph/9602078v1
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Sep 20, 2013
09/13
by
John N. Bahcall; Sofia Kirhakos; David H. Saxe; Donald P. Schneider
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Observations with the Wide-Field Camera of the Hubble Space Telescope are presented for a representative sample of 20 intrinsically luminous quasars with redshifts smaller than 0.30. These observations show that luminous quasars occur in diverse environments that include ellipticals as bright as the brightest cluster galaxies (2), apparently normal ellipticals (10), apparently normal spirals with H II regions (3), complex systems of gravitationally interacting components (3), and faint...
Source: http://arxiv.org/abs/astro-ph/9611163v2
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Sep 23, 2013
09/13
by
Daniel W. Weedman; Jeffrey B. Wolovitz; Matthew A. Bershady; Donald P. Schneider
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Observations in the rest frame ultraviolet from various space missions are used to define the nearby starburst regions having the highest surface brightness on scales of several hundred pc. The bright limit is found to be 6x10^-16 ergs/cm^2-s-A-arcsec^2 for rest frame wavelength of 1830 A. Surface brightness in the brightest pixel is measured for 18 galaxies in the Hubble Deep Field having z > 2.2. After correcting for cosmological dimming, we find that the high redshift starbursts have...
Source: http://arxiv.org/abs/astro-ph/9806398v1
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43
Sep 21, 2013
09/13
by
Robert R. Gibson; W. N. Brandt; Donald P. Schneider; S. C. Gallagher
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eye 43
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We use quantitative metrics to characterize the variation of CIV 1549 A broad absorption lines (BALs) over 3--6 (rest-frame) years in a sample of 13 quasars at 1.7
Source: http://arxiv.org/abs/0712.1831v1
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86
Sep 21, 2013
09/13
by
Robert R. Gibson; W. N. Brandt; S. C. Gallagher; Donald P. Schneider
texts
eye 86
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We examine the UV and X-ray properties of 256 radio-quiet SDSS quasars (QSOs) observed in X-rays with Chandra and/or XMM-Newton in order to study the relationship between QSOs with broad CIV absorption lines (BALs; width >2000 km/s) and those with CIV mini-BALs (here defined to have widths of 1000--2000 km/s). Our sample includes 42 BAL and 48 mini-BAL QSOs. The relative X-ray brightness and hard spectral slopes of the mini-BAL population are, on average, intermediate between those of BAL...
Source: http://arxiv.org/abs/0902.0951v1
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50
Sep 19, 2013
09/13
by
Beth Willman; Julianne Dalcanton; Zeljko Ivezic; Donald P. Schneider; Donald G. York
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eye 50
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In this paper, we limit the stellar content of 13 high-velocity clouds (HVCs; including 1 compact HVC) using the detection limits of a new survey for resolved Milky Way satellite galaxies in the Sloan Digital Sky Survey Early Data Release (EDR). Our analysis is sensitive to stellar associations within the virial radius of the Milky Way that are up to 50 times fainter than the faintest known Milky Way satellites. Statistically, we find no stellar overdensity associated with any of the clouds....
Source: http://arxiv.org/abs/astro-ph/0208260v1
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40
Sep 20, 2013
09/13
by
Junfeng Wang; Patrick B. Hall; Jian Ge; Aigen Li; Donald P. Schneider
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eye 40
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The strongest spectroscopic dust extinction feature in the Milky Way, the broad absorption bump at 2175 \AA, is generally believed to be caused by aromatic carbonaceous materials -- very likely a mixture of Polycyclic Aromatic Hydrocarbon (PAH) molecules, the most abundant and widespread organic molecules in the Milky Way galaxy. In this paper we report identifications of this absorption feature in three galaxies at $1.4 \lesssim z \lesssim 1.5$ which produce intervening MgII absorption toward...
Source: http://arxiv.org/abs/astro-ph/0404151v1
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Jun 28, 2018
06/18
by
Daniel Margala; David Kirkby; Kyle Dawson; Stephen Bailey; Michael Blanton; Donald P. Schneider
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We present a model for spectrophotometric calibration errors in observations of quasars from the third generation of the Sloan Digital Sky Survey (SDSS-III) Baryon Oscillation Spectroscopic Survey (BOSS) and describe the correction procedure we have developed and applied to this sample. Calibration errors are primarily due to atmospheric differential refraction and guiding offsets during each exposure. The corrections potentially reduce the systematics for any studies of BOSS quasars, including...
Topics: Instrumentation and Methods for Astrophysics, Astrophysics, Cosmology and Nongalactic Astrophysics
Source: http://arxiv.org/abs/1506.04790
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78
Sep 22, 2013
09/13
by
Puragra Guhathakurta; Zodiac T. Webster; Brian Yanny; Donald P. Schneider; John N. Bahcall
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eye 78
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We present F555W (V), F439W (B), and F336W (U) photometry of 9507 stars in the central 2' of the dense, post core collapse cluster M30 (NGC 7099) derived from HST WFPC2 images. These data are used to study the mix of stellar populations in the central region of the cluster. Forty eight blue straggler stars are identified and are found to be strongly concentrated towards the center. The specific frequency of blue stragglers, F_BSS\equiv N(BSS)/N(V
Source: http://arxiv.org/abs/astro-ph/9805361v1
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34
Sep 20, 2013
09/13
by
Randi L. Cohen; Puragra Guhathakurta; Brian Yanny; Donald P. Schneider; John N. Bahcall
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To probe the nature of stellar evolution in dense environments, we study the dense core of the globular cluster Messier 13 using pre-refurbishment Planetary Camera-I images obtained with the Hubble Space Telescope. We find 15 blue straggler star candidates and 10 other possible blue stragglers in this region of M13. Their specific frequency is in the range 0.04-0.07, comparable to what is observed near the centers of other dense clusters. A comparison between M13's observed V band stellar...
Source: http://arxiv.org/abs/astro-ph/9611151v1
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61
Sep 22, 2013
09/13
by
Andrew W. Stephens; Donald P. Schneider; Maarten Schmidt; James E. Gunn; David H. Weinberg
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eye 61
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The quest for structure indicators at earlier and earlier times in the evolution of the universe has led to the search for objects with ever higher redshifts. The Palomar Transit Grism Survey has produced a large sample of high redshift quasars ($z>2.7$), allowing statistical analysis of correlation between quasar positions. In this study, clustering is identified through comparison with $100 000$ Monte Carlo generated, randomly populated volumes, which are identical to the observed region...
Source: http://arxiv.org/abs/astro-ph/9708241v1
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Jun 27, 2018
06/18
by
Felipe A. Marín; Florian Beutler; Chris Blake; Jun Koda; Eyal Kazin; Donald P. Schneider
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eye 18
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The anisotropic galaxy 2-point correlation function (2PCF) allows measurement of the growth of large-scale structures from the effect of peculiar velocities on the clustering pattern. We present new measurements of the auto- and cross- correlation function multipoles of 69,180 WiggleZ and 46,380 BOSS-CMASS galaxies sharing an overlapping volume of ~0.2 (Gpc/h)^3. Analysing the redshift-space distortions (RSD) of galaxy 2-point statistics for these two galaxy tracers, we test for systematic...
Topics: Cosmology and Nongalactic Astrophysics, Astrophysics
Source: http://arxiv.org/abs/1506.03901
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64
Sep 18, 2013
09/13
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Shai Kaspi; Hagai Netzer; Dan Maoz; Ohad Shemmer; W. N. Brandt; Donald P. Schneider
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We present preliminary results from a reverberation mapping program to measure the Broad Line Region size in high-redshift, high-luminosity quasars. The observations are carried out at the Hobby-Eberly Telescope and at the Wise Observatory. The data cover 8 yr of photometric monitoring of 11 quasars, and 2.5 yr of spectrophotometric monitoring of 7 of these sources. Thus far we detected continuum variations but no line variations. We find that the continua of the high-luminosity quasars have...
Source: http://arxiv.org/abs/astro-ph/0210633v1
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61
Sep 21, 2013
09/13
by
Yue Shen; Jenny E. Greene; Michael A. Strauss; Gordon T. Richards; Donald P. Schneider
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eye 61
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We compile black hole (BH) masses for $\sim 60,000$ quasars in the redshift range $0.1 \lesssim z \lesssim 4.5$ included in the Fifth Data Release of the Sloan Digital Sky Survey (SDSS), using virial BH mass estimators based on the \hbeta, \MgII, and \CIV emission lines. We find that: (1) within our sample, the widths of the three lines follow log-normal distributions, with means and dispersions that do not depend strongly on luminosity or redshift;(2) the \MgII- and \hbeta-estimated BH masses...
Source: http://arxiv.org/abs/0709.3098v2
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49
Sep 20, 2013
09/13
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Nikhil Padmanabhan; Christopher M. Hirata; Uros Seljak; David Schlegel; Jonathan Brinkmann; Donald P. Schneider
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eye 49
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We present a 2.5 sigma detection of the Integrated Sachs-Wolfe (ISW) effect and discuss the constraints it places on cosmological parameters. We cross-correlate microwave temperature maps from the WMAP satellite with a 4000 deg^2 luminous red galaxy (LRG) overdensity map measured by the Sloan Digital Sky Survey. Accurate photometric redshifts allow us to perform a reliable auto-correlation analysis of the LRGs, eliminating the uncertainty in the galaxy bias, and combined with cross correlation...
Source: http://arxiv.org/abs/astro-ph/0410360v1
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66
Sep 20, 2013
09/13
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Shai Kaspi; W. N. Brandt; Dan Maoz; Hagai Netzer; Donald P. Schneider; Ohad Shemmer
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Reverberation mapping of nearby active galactic nuclei has led to estimates of broad-line-region (BLR) sizes and central-object masses for some 37 objects to date. However, successful reverberation mapping has yet to be performed for quasars of either high luminosity (above L_opt~10^{46} erg/s) or high redshift (z>0.3). Over the past six years, we have carried out, at the Hobby-Eberly Telescope, rest-frame-ultraviolet spectrophotometric monitoring of a sample of six quasars at redshifts...
Source: http://arxiv.org/abs/astro-ph/0612722v1
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10.0
Jun 30, 2018
06/18
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Surhud More; Hironao Miyatake; Rachel Mandelbaum; Masahiro Takada; David Spergel; Joel Brownstein; Donald P. Schneider
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We perform a joint analysis of the abundance, the clustering and the galaxy-galaxy lensing signal of galaxies measured from Data Release 11 of the Sloan Digital Sky Survey III Baryon Oscillation Spectroscopic Survey (SDSS III-BOSS) in our companion paper, Miyatake et al. (2014). The lensing signal was obtained by using the shape catalog of background galaxies from the Canada France Hawaii Telescope Legacy Survey, which was made publicly available by the CFHTLenS collaboration, with an area...
Topics: Astrophysics, Cosmology and Nongalactic Astrophysics
Source: http://arxiv.org/abs/1407.1856
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Sep 17, 2013
09/13
by
Robert R. Gibson; W. N. Brandt; S. C. Gallagher; Paul C. Hewett; Donald P. Schneider
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We investigate the variability of CIV 1549A broad absorption line (BAL) troughs over rest-frame time scales of up to ~7 yr in 14 quasars at redshifts z>2.1. For 9 sources at sufficiently high redshift, we also compare CIV and SiIV 1400A absorption variation. We compare shorter- and longer-term variability using spectra from up to four different epochs per source and find complex patterns of variation in the sample overall. The scatter in the change of absorption equivalent width (EW), Delta...
Source: http://arxiv.org/abs/1003.5600v1
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8.0
Jun 29, 2018
06/18
by
Lile Wang; Jenny E. Greene; Wenhua Ju; Roman R. Rafikov; John J. Ruan; Donald P. Schneider
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Supermassive black hole binaries (SMBHs) are expected to result from galaxy mergers, and thus are natural byproducts (and probes) of hierarchical structure formation in the Universe. They are also the primary expected source of low-frequency gravitational wave emission. We search for binary BHs using time-variable velocity shifts in broad Mg II emission lines of quasars with multi-epoch observations. First, we inspect velocity shifts of the binary SMBH candidates identified in Ju et al. (2013),...
Topics: Astrophysics, Cosmology and Nongalactic Astrophysics, Astrophysics of Galaxies
Source: http://arxiv.org/abs/1611.00039
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47
Sep 21, 2013
09/13
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Jianfeng Wu; W. N. Brandt; Brendan P. Miller; Gordon P. Garmire; Donald P. Schneider; Cristian Vignali
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(Abridged) We present a systematic study of the X-ray and multiwavelength properties of a sample of 17 highly radio-loud quasars (HRLQs) at z > 4 with sensitive X-ray coverage from new Chandra and archival Chandra, XMM-Newton, and Swift observations. Eight of the new and archival observations are reported in this work for the first time. New Chandra observations of two moderately radio-loud and highly optically luminous quasars at z > 4 are also reported. Our HRLQ sample represents the...
Source: http://arxiv.org/abs/1301.0012v1
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Sep 18, 2013
09/13
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Osamu Nakamura; Masataka Fukugita; Naoki Yasuda; Jon Loveday; Jon Brinkmann; Donald P. Schneider; Kazuhiro Shimasaku; Mark SubbaRao
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The morphological dependence of the luminosity function is studied using a sample containing approximately 1500 bright galaxies classified into Hubble types by visual inspections for a homogeneous sample obtained from the Sloan Digital Sky Survey (SDSS) northern equatorial stripes. Early-type galaxies are shown to have a characteristic magnitude by 0.45 mag brighter than spiral galaxies in the $r^{\ast}$ band, consistent with the `universal characteristic luminosity' in the $B$ band. The shape...
Source: http://arxiv.org/abs/astro-ph/0212405v1
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3.0
Jun 30, 2018
06/18
by
Héctor Gil-Marín; Jorge Noreña; Licia Verde; Will J. Percival; Christian Wagner; Marc Manera; Donald P. Schneider
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We analyse the anisotropic clustering of the Baryon Oscillation Spectroscopic Survey (BOSS) CMASS Data Release 11 sample, which consists of $690 827$ galaxies in the redshift range $0.43 < z < 0.70$ and has a sky coverage of $8 498$ deg$^2$ corresponding to an effective volume of $\sim6\,\rm{Gpc}^3$. We fit the Fourier space statistics, the power spectrum and bispectrum monopoles to measure the linear and quadratic bias parameters, $b_1$ and $b_2$, for a non-linear non-local bias model,...
Topics: Astrophysics of Galaxies, Astrophysics, Cosmology and Nongalactic Astrophysics
Source: http://arxiv.org/abs/1407.5668
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Sep 23, 2013
09/13
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Richard J. Cool; Daniel J. Eisenstein; David Johnston; Ryan Scranton; Jon Brinkmann; Donald P. Schneider; Idit Zehavi
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eye 46
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Using a sample of nearly 20,000 massive early-type galaxies selected from the Sloan Digital Sky Survey, we study the color-magnitude relation for the most luminous (L > 2.2 L^{*}) field galaxies in the redshift range 0.1
Source: http://arxiv.org/abs/astro-ph/0510301v1
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Sep 22, 2013
09/13
by
Neta A. Bahcall; Feng Dong; Lei Hao; Paul Bode; Jim Annis; James E. Gunn; Donald P. Schneider
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The cluster correlation function and its richness dependence are determined from 1108 clusters of galaxies -- the largest sample of clusters studied so far -- found in 379 deg^2 of Sloan Digital Sky Survey early data. The results are compared with previous samples of optically and X-ray selected clusters. The richness-dependent correlation function increases monotonically from an average correlation scale of ~ 12 h^{-1} Mpc for poor clusters to ~ 25 h^{-1} Mpc for the richer, more massive...
Source: http://arxiv.org/abs/astro-ph/0307102v2
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78
Sep 18, 2013
09/13
by
Dan Maoz; Alexei V. Filippenko; Luis C. Ho; F. Duccio Macchetto; Hans-Walter Rix; Donald P. Schneider
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We present an atlas of UV ($\sim 2300$ \AA) images, obtained with the Hubble Space Telescope (HST) Faint Object Camera, of the central $22''\times 22''$ of 110 galaxies. The observed galaxies are an unbiased selection constituting about one half of a complete sample of all large ($D>6'$) and nearby ($V < 2000$ km s$^{-1}$) galaxies. This is the first extensive UV imaging survey of normal galaxies. The data are useful for studying star formation, low-level nuclear activity, and UV emission...
Source: http://arxiv.org/abs/astro-ph/9605170v1
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120
Sep 17, 2013
09/13
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Teppei Okumura; Takahiko Matsubara; Daniel J. Eisenstein; Issha Kayo; Chiaki Hikage; Alexander S. Szalay; Donald P. Schneider
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We study the large-scale anisotropic two-point correlation function using 46,760 luminous red galaxies at redshifts 0.16 -- 0.47 from the Sloan Digital Sky Survey. We measure the correlation function as a function of separations parallel and perpendicular to the line-of-sight in order to take account of anisotropy of the large-scale structure in redshift space. We find a slight signal of baryonic features in the anisotropic correlation function, i.e., a ``baryon ridge'' which corresponds to a...
Source: http://arxiv.org/abs/0711.3640v2
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48
Sep 21, 2013
09/13
by
Ari Laor; John N. Bahcall; Buell T. Jannuzi; Donald P. Schneider; Richard F. Green; George F. Hartig
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We analyze the ultraviolet (UV) emission line and continuum properties of five low-redshift active galactic nuclei (four luminous quasars: PKS~0405$-$123, H1821+643, PG~0953+414, and 3C273, and one bright Seyfert 1 galaxy: Mrk~205). The HST spectra have higher signal-to-noise ratios (typically $\sim 60$ per resolution element) and spectral resolution ($R = 1300$) than all previously- published UV spectra used to study the emission characteristics of active galactic nuclei. We include in the...
Source: http://arxiv.org/abs/astro-ph/9305026v1
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90
Sep 17, 2013
09/13
by
Helen M. Johnston; Elaine M. Sadler; Russell Cannon; Scott M. Croom; Nicholas P. Ross; Donald P. Schneider
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We present an analysis of the optical spectra of a volume-limited sample of 375 radio galaxies at redshift 0.4 10^26 W/Hz) have younger stars and stronger emission lines than the less powerful sources. This suggests that we have located the threshold in radio power where strong emission lines "switch on", at radio powers of around 10^26 W/Hz. Except for the very powerful radio galaxies, the presence of a currently-active radio AGN does not appear to be correlated with any change in...
Source: http://arxiv.org/abs/0711.3486v1
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41
Sep 19, 2013
09/13
by
David Syphers; Scott F. Anderson; Wei Zheng; Daryl Haggard; Avery Meiksin; Donald P. Schneider; Donald G. York
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Absorption along quasar sightlines remains among the most sensitive direct measures of HeII reionization in much of the intergalactic medium (IGM). Until recently, fewer than a half-dozen unobscured quasar sightlines suitable for the HeII Gunn-Peterson test were known; although these handful demonstrated great promise, the small sample size limited confidence in cosmological inferences. We have recently added nine more such clean HeII quasars, exploiting SDSS quasar samples, broadband UV...
Source: http://arxiv.org/abs/0909.3962v1
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6.0
Jun 29, 2018
06/18
by
Naohiro Takanashi; Mamoru Doi; Naoki Yasuda; Hanindyo Kuncarayakti; Kohki Konishi; Donald P. Schneider; David Cinabro; John Marriner
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We have analyzed multi-band light curves of 328 intermediate redshift (0.05 2.5) don't have a broad light curve width and the SNe Ia which appeared in blue host galaxies (u - r < 2.0) have a variety of light curve widths. The Kolmogorov-Smirnov test shows that the colour distribution of SNe Ia appeared in red / blue host galaxies is different (significance level of 99.9%). We also investigate the extinction law of host galaxy dust. As a result, we find the value of Rv derived from SNe Ia...
Topics: Astrophysics, Cosmology and Nongalactic Astrophysics, Astrophysics of Galaxies
Source: http://arxiv.org/abs/1610.06396
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11
Jun 27, 2018
06/18
by
Florian Beutler; Chris Blake; Jun Koda; Felipe Marin; Hee-Jong Seo; Antonio J. Cuesta; Donald P. Schneider
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We study the large-scale clustering of galaxies in the overlap region of the Baryon Oscillation Spectroscopic Survey (BOSS) CMASS sample and the WiggleZ Dark Energy Survey. We calculate the auto-correlation and cross-correlation functions in the overlap region of the two datasets and detect a Baryon Acoustic Oscillation (BAO) signal in each of them. The BAO measurement from the cross-correlation function represents the first such detection between two different galaxy surveys. After applying...
Topics: Cosmology and Nongalactic Astrophysics, Astrophysics
Source: http://arxiv.org/abs/1506.03900
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39
Sep 17, 2013
09/13
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Issha Kayo; Naohisa Inada; Masamune Oguri; Tomoki Morokuma; Patrick B. Hall; Christopher S. Kochanek; Donald P. Schneider
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We report the discovery and confirmation of eight new two-image lensed quasars by the Sloan Digital Sky Survey (SDSS) Quasar Lens Search. The lenses are SDSSJ0904+1512 (image separation \theta=1"13, source redshift z_s=1.826), SDSSJ1054+2733 (\theta=1"27, z_s=1.452), SDSSJ1055+4628 (\theta=1"15, z_s=1.249), SDSSJ1131+1915 (\theta=1"46, z_s=2.915), SDSSJ1304+2001 (\theta=1"87, z_s=2.175), SDSSJ1349+1227 (\theta=3"00, z_s=1.722), SDSSJ1455+1447 (\theta=1"73,...
Source: http://arxiv.org/abs/0912.1462v2
