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Related papers: HI intensity mapping : a single dish approach

200 papers

We present an analysis of the HI absorption in a sample of 101 flux-selected radio AGN (S_1.4 GHz > 50 mJy) observed with the Westerbork Synthesis Radio Telescope (WSRT). HI absorption is detected in 32 galaxies, showing a broad variety of…

Astrophysics of Galaxies · Physics 2015-06-23 K. Gereb , F. M. Maccagni , R. Morganti , T. A. Oosterloo

Intensity mapping of 21-cm line by several radio telescope experiments will probe the large-scale structure of the Universe in the post-reionization epoch. It requires a theoretical framework of neutral hydrogen (HI) clustering, such as…

Cosmology and Nongalactic Astrophysics · Physics 2021-08-18 Rika Ando , Atsushi J Nishizawa , Shimizu Ikkoh , Kentaro Nagamine

The Baryon Acoustic Oscillations (BAO) phenomenon provides a unique opportunity to establish a standard ruler at any epoch in the history of the evolving universe. The key lies in identifying a suitable cosmological tracer to conduct the…

Cosmology and Nongalactic Astrophysics · Physics 2024-06-13 Felipe Avila , Edilson de Carvalho , Armando Bernui , Hanna Lima , Rafael C. Nunes

We use a large N-body simulation to examine the detectability of HI in emission at redshift z ~ 1, and the constraints imposed by current observations on the neutral hydrogen mass function of galaxies at this epoch. We consider three…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 Nishikanta Khandai , Shiv K. Sethi , Tiziana Di Matteo , Rupert A. C. Croft , Volker Springel , Anirban Jana , Jeffrey P. Gardner

Baryonic Acoustic Oscillations (BAO) and their effects on the matter power spectrum can be studied by using the Lyman-alpha absorption signature of the matter density field along quasar (QSO) lines of sight. A measurement sufficiently…

Cosmology and Nongalactic Astrophysics · Physics 2009-10-21 Ch. Yeche , P. Petitjean , J. Rich , E. Aubourg , N. Busca , J. -Ch. Hamilton , J. -M. Le Goff , I. Paris , S. Peirani , Ch. Pichon , E. Rollinde , M. Vargas-Magana

4C+15.05, (also known as NRAO 91, PKS 0202+14 or J0204+15), is a quintessential blazar. It has a luminous, variable radio spectrum, a super-luminal jet, and gamma-ray detections. Arecibo observations with the 700-800 MHz receiver on the…

Astrophysics of Galaxies · Physics 2018-07-26 Kristen M. Jones , Tapasi Ghosh , Chris J. Salter

Cross-correlating neutral hydrogen (HI) 21cm intensity mapping with galaxy surveys provides an effective probe of astrophysical and cosmological information. This work presents a cross-correlation analysis between MeerKAT single-dish HI…

Cosmology and Nongalactic Astrophysics · Physics 2026-02-12 Yu-Er Jiang , Yan Gong , Qi Xiong , Wenxiang Pei , Yun Liu , Furen Deng , Zi-yan Yuwen , Meng Zhang , Xingchen Zhou , Xuelei Chen , Yin-Zhe Ma , Qi Guo , Bin Yue

The redshifted 21-cm monopole is expected to be a powerful probe of the epoch of the first stars and galaxies ($10<z<35$). The global 21-cm signal is sensitive to the thermal and ionization state of hydrogen gas and thus provides a tracer…

Baryon acoustic oscillations (BAO) in the galaxy power spectrum allows us to extract the scale of the comoving sound horizon at recombination, a cosmological standard ruler accurately determined by the cosmic microwave background anisotropy…

Astrophysics · Physics 2008-11-26 Yun Wang

Large redshift surveys capable of measuring the Baryon Acoustic Oscillation (BAO) signal have proven to be an effective way of measuring the distance-redshift relation in cosmology. Building off the work in Zhu et al. (2015), we develop a…

Cosmology and Nongalactic Astrophysics · Physics 2016-07-27 Fangzhou Zhu , Nikhil Padmanabhan , Martin White , Ashley J. Ross , Gongbo Zhao

The FAST All Sky H I survey (FASHI) will cover the entire observable sky ($\sim$22000 square degrees) with the Five-hundred-meter Aperture Spherical radio Telescope (FAST). With the currently released data, we perform an untargeted survey…

Astrophysics of Galaxies · Physics 2024-12-13 Chuan-Peng Zhang , Ming Zhu , Peng Jiang , Cheng Cheng , Jin-Long Xu , Nai-Ping Yu , Xiao-Lan Liu , Bo Zhang

The measurement of baryon acoustic oscillations (BAO) from a galaxy redshift survey provides one of the most promising methods for probing dark energy. In this paper, we clarify the assumptions that go into the forecasts of dark energy…

Cosmology and Nongalactic Astrophysics · Physics 2010-11-23 Yun Wang

This paper describes a programme to map large-scale cosmic structures on the largest possible scales by using the Five hundred metre Aperture Spherical Telescope (FAST) to make a 21 cm (red-shifted) intensity map of the sky for the range…

Cosmology and Nongalactic Astrophysics · Physics 2017-01-25 George F. Smoot , Ivan Debono

Telescopes aiming to measure 21cm emission from the Epoch of Reionization must toe a careful line, balancing the need for raw sensitivity against the stringent calibration requirements for removing bright foregrounds. It is unclear what the…

Instrumentation and Methods for Astrophysics · Physics 2015-05-27 Aaron Parsons , Jonathan Pober , Matthew McQuinn , Daniel Jacobs , James Aguirre

The Arecibo Ultra Deep Survey (AUDS) is a blind HI survey aimed at detecting galaxies beyond the local Universe in the 21-cm emission line of neutral hydrogen (HI). The Arecibo $L$-band Feed Array (ALFA) was used to image an area of…

Astrophysics of Galaxies · Physics 2021-01-06 Hongwei Xi , Lister Staveley-Smith , Bi-Qing For , Wolfram Freudling , Martin Zwaan , Laura Hoppmann , Fu-Heng Liang , Bo Peng

Baryon Acoustic Oscillations (BAO) allow us to determine the expansion history of the Universe, thereby shedding light on the nature of dark energy. Recent observations of BAO's in the SDSS DR9 and DR11 have provided us with statistically…

Cosmology and Nongalactic Astrophysics · Physics 2014-09-25 Varun Sahni , Arman Shafieloo , Alexei A. Starobinsky

The EXperiment for Cryogenic Large-Aperture Intensity Mapping (EXCLAIM) is a balloon-borne cryogenic telescope that will survey the spectrum of diffuse emission from both the Milky Way and the cosmic web to probe star formation, the…

We present measurements of the baryon acoustic peak at redshifts z = 0.44, 0.6 and 0.73 in the galaxy correlation function of the final dataset of the WiggleZ Dark Energy Survey. We combine our correlation function with lower-redshift…