中文
相关论文

相关论文: A 21-cm power spectrum at 48 MHz, using the Owens …

200 篇论文

The redshifted 21 cm signal from neutral hydrogen is a direct probe of the physics of the early universe and has been an important science driver of many present and upcoming radio interferometers. In this study we use a single night of…

The Epoch of Reionization (EoR)---when neutral hydrogen in the intergalactic medium was systematically ionized---is a period in our Universe's history that is currently poorly understood. However, a key prediction of most models is a…

宇宙学与河外天体物理 · 物理学 2021-05-25 Michael Pagano , Adrian Liu

We measure the large-scale real-space power spectrum P(k) using a sample of 205,443 galaxies from the Sloan Digital Sky Survey, covering 2417 square degrees with mean redshift z~0.1. We employ a matrix-based method using…

To continue the unparalleled success of the Very Large Array (VLA) for radio astronomy, the facility is currently being converted to become the 'Expanded VLA' (EVLA). The EVLA will radically improve the VLA in order to cover the full…

天体物理学 · 物理学 2009-11-13 Juergen Ott , Rick Perley , Michael Rupen , the EVLA team

Spectral measurements of the 21 cm monopole background have the promise of revealing the bulk energetic properties and ionization state of our universe from z ~ 6-30. Synchrotron foregrounds are orders of magnitude larger than the…

宇宙学与河外天体物理 · 物理学 2014-10-08 Eric R. Switzer , Adrian Liu

Observations of redshifted 21-cm radiation from neutral hydrogen during the epoch of reionization (EoR) are considered to constitute the most promising tool to probe that epoch. One of the major goals of the first generation of low…

宇宙学与河外天体物理 · 物理学 2015-05-30 Kanan K. Datta , Garrelt Mellema , Yi Mao , Ilian T. Iliev , Paul R. Shapiro , Kyungjin Ahn

We have analyzed a large set of RXTE/PCA scanning and slewing observations performed between April 1996 and March 1999. We obtained the 3-20 keV spectrum of the cosmic X-ray background (CXB) by subtracting Earth-occulted observations from…

天体物理学 · 物理学 2009-11-10 M. Revnivtsev , M. Gilfanov , R. Sunyaev , K. Jahoda , C. Markwardt

The global 21 cm signal from Cosmic Dawn (CD) and the Epoch of Reionization (EoR), at redshifts $z \sim 6-30$, probes the nature of first sources of radiation as well as physics of the Inter-Galactic Medium (IGM). Given that the signal is…

We measure the large-scale real-space power spectrum P(k) using luminous red galaxies (LRGs) in the Sloan Digital Sky Survey (SDSS) and use this measurement to sharpen constraints on cosmological parameters from the Wilkinson Microwave…

A number of experiments are currently working towards a measurement of the 21 cm signal from the Epoch of Reionization. Whether or not these experiments deliver a detection of cosmological emission, their limited sensitivity will prevent…

A measurement with high statistics of the differential energy spectrum of light elements in cosmic rays, in particular, of primary H plus He nuclei, is reported. The spectrum is presented in the energy range from $6$ to $158$ TeV per…

This paper presents the spherically-averaged 21 cm power spectrum derived from Epoch of Reionization (EoR) observations conducted with the Murchison Widefield Array (MWA). The analysis uses EoR0-field data, centered at (RA$=0h$,…

We use the newly released 182 Type Ia supernova data combined with the third-year Wilkinson Microwave Anisotropic Probe data (WMAP3) and large scale structure (LSS) information including SDSS and 2dFGRS to constrain the dark energy equation…

天体物理学 · 物理学 2008-11-26 Gong-Bo Zhao , Jun-Qing Xia , Hong Li , Charling Tao , Jean-Marc Virey , Zong-Hong Zhu , Xinmin Zhang

Deep radio observations at 1.4GHz for the Extended Chandra Deep Field South were performed in June through September of 2007 and presented in a first data release (Miller et al. 2008). The survey was made using six separate pointings of the…

宇宙学与河外天体物理 · 物理学 2015-06-12 N. A. Miller , M. Bonzini , E. B. Fomalont , K. I. Kellermann , V. Mainieri , P. Padovani , P. Rosati , P. Tozzi , S. Vattakunnel

Large High Altitude Air Shower Observatory(LHAASO) is a composite cosmic ray observatory consisting of three detector arrays: kilometer square array (KM2A) which includes the electromagnetic detector array and muon detector array, water…

高能天体物理现象 · 物理学 2019-04-22 L. Q. Yin , S. S. Zhang , Z. Cao , B. Y. Bi , C. Wang , J. L. Liu , L. L. Ma , M. J. Yang , Tiina Suomijarvi , Y. Zhang , Z. Y. You , Z. Z Zong

Current surveys may be on the verge of measuring the baryonic oscillations in the galaxy power spectrum which are clearly seen imprinted on the Cosmic Microwave Background. It has recently been proposed that these oscillations allow a…

天体物理学 · 物理学 2009-11-10 F. B. Abdalla , S. Rawlings

The redshifted 21cm line signal from neutral hydrogens is a promising tool to probe the cosmic dawn and the epoch of reionization (EoR). Ongoing and future low-frequency radio experiments are expected to detect its fluctuations, especially…

宇宙学与河外天体物理 · 物理学 2015-06-16 Hayato Shimabukuro , Shintaro Yoshiura , Keitaro Takahashi , Shuichiro Yokoyama , Kiyotomo Ichiki

A comparison between the line of sight power spectrum of absorption in the Lyman-alpha forest and the cross power spectrum between the absorption in neighboring lines of sight offers an evolution-free means to constrain the cosmological…

天体物理学 · 物理学 2007-05-23 Adam Lidz , Lam Hui , Arlin P. S. Crotts , Matias Zaldarriaga

We theoretically investigate the recovery of global spectrum (monopole) from visibilities (cross-correlation only) measured by the interferometer array and the feasibility of extracting 21 cm signal of cosmic dawn. In our approach, the…

宇宙学与河外天体物理 · 物理学 2023-03-29 Xin Zhang , Bin Yue , Yuan Shi , Fengquan Wu , Xuelei Chen

We measure seeing-corrected ellipticities for 2 x 10^6 galaxies with magnitude R<23 in 12 widely separated fields totalling 75 deg^2 of sky. At angular scales >30\arcmin, ellipticity correlations are detected at high significance and…

天体物理学 · 物理学 2015-06-24 M. Jarvis , G. Bernstein , B. Jain , P. Fischer , D. Smith , J. A. Tyson , D. Wittman