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Title: THE ARECIBO LEGACY FAST ALFA SURVEY. X. THE H I MASS FUNCTION AND {Omega}{sub H{sub i}} FROM THE 40% ALFALFA SURVEY

Abstract

The Arecibo Legacy Fast ALFA (ALFALFA) survey has completed source extraction for 40% of its total sky area, resulting in the largest sample of H I-selected galaxies to date. We measure the H I mass function from a sample of 10,119 galaxies with 6.2 < log (M{sub H{sub i}}/M{sub sun}) < 11.0 and with well-described mass errors that accurately reflect our knowledge of low-mass systems. We characterize the survey sensitivity and its dependence on profile velocity width, the effect of large-scale structure, and the impact of radio frequency interference in order to calculate the H I mass function with both the 1/V{sub max} and 2DSWML methods. We also assess a flux-limited sample to test the robustness of the methods applied to the full sample. These measurements are in excellent agreement with one another; the derived Schechter function parameters are {phi}{sub *} (h {sup 3}{sub 70} Mpc{sup -3} dex{sup -1}) = 4.8 {+-} 0.3 x 10{sup -3}, log (M{sub *}/M{sub sun}) + 2 log h{sub 70} = 9.96 {+-} 0.02, and {alpha} = -1.33 {+-} 0.02. We find {Omega}{sub H{sub i}}= 4.3 {+-} 0.3 x10{sup -4} h {sup -1}{sub 70}, 16% larger than the 2005 HIPASS result, and our Schechter functionmore » fit extrapolated to log (M{sub H{sub i}}/M{sub sun}) = 11.0 predicts an order of magnitude more galaxies than HIPASS. The larger values of {Omega}{sub H{sub i}} and of M{sub *} imply an upward adjustment for estimates of the detection rate of future large-scale H I line surveys with, e.g., the Square Kilometer Array. A comparison with simulated galaxies from the Millennium Run and a treatment of photoheating as a method of baryon removal from H I-selected halos indicate that the disagreement between dark matter mass functions and baryonic mass functions may soon be resolved.« less

Authors:
; ; ;  [1];  [2];  [3]
  1. Center for Radiophysics and Space Research, Space Sciences Building, Cornell University, Ithaca, NY 14853 (United States)
  2. Australian Astronomical Observatory, P.O. Box 296, Epping, NSW 1710 (Australia)
  3. Spitzer Science Center, California Institute of Technology, 1200 East California Boulevard, CA 91125 (United States)
Publication Date:
OSTI Identifier:
21471261
Resource Type:
Journal Article
Journal Name:
Astrophysical Journal
Additional Journal Information:
Journal Volume: 723; Journal Issue: 2; Other Information: DOI: 10.1088/0004-637X/723/2/1359; Journal ID: ISSN 0004-637X
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; BARYONS; DWARF STARS; GALAXIES; INTERFERENCE; LUMINOSITY; MASS; NONLUMINOUS MATTER; RADIOWAVE RADIATION; RED SHIFT; ELECTROMAGNETIC RADIATION; ELEMENTARY PARTICLES; FERMIONS; HADRONS; MATTER; OPTICAL PROPERTIES; PHYSICAL PROPERTIES; RADIATIONS; STARS

Citation Formats

Martin, Ann M, Papastergis, Emmanouil, Giovanelli, Riccardo, Haynes, Martha P, Springob, Christopher M, and Stierwalt, Sabrina. THE ARECIBO LEGACY FAST ALFA SURVEY. X. THE H I MASS FUNCTION AND {Omega}{sub H{sub i}} FROM THE 40% ALFALFA SURVEY. United States: N. p., 2010. Web. doi:10.1088/0004-637X/723/2/1359.
Martin, Ann M, Papastergis, Emmanouil, Giovanelli, Riccardo, Haynes, Martha P, Springob, Christopher M, & Stierwalt, Sabrina. THE ARECIBO LEGACY FAST ALFA SURVEY. X. THE H I MASS FUNCTION AND {Omega}{sub H{sub i}} FROM THE 40% ALFALFA SURVEY. United States. https://doi.org/10.1088/0004-637X/723/2/1359
Martin, Ann M, Papastergis, Emmanouil, Giovanelli, Riccardo, Haynes, Martha P, Springob, Christopher M, and Stierwalt, Sabrina. 2010. "THE ARECIBO LEGACY FAST ALFA SURVEY. X. THE H I MASS FUNCTION AND {Omega}{sub H{sub i}} FROM THE 40% ALFALFA SURVEY". United States. https://doi.org/10.1088/0004-637X/723/2/1359.
@article{osti_21471261,
title = {THE ARECIBO LEGACY FAST ALFA SURVEY. X. THE H I MASS FUNCTION AND {Omega}{sub H{sub i}} FROM THE 40% ALFALFA SURVEY},
author = {Martin, Ann M and Papastergis, Emmanouil and Giovanelli, Riccardo and Haynes, Martha P and Springob, Christopher M and Stierwalt, Sabrina},
abstractNote = {The Arecibo Legacy Fast ALFA (ALFALFA) survey has completed source extraction for 40% of its total sky area, resulting in the largest sample of H I-selected galaxies to date. We measure the H I mass function from a sample of 10,119 galaxies with 6.2 < log (M{sub H{sub i}}/M{sub sun}) < 11.0 and with well-described mass errors that accurately reflect our knowledge of low-mass systems. We characterize the survey sensitivity and its dependence on profile velocity width, the effect of large-scale structure, and the impact of radio frequency interference in order to calculate the H I mass function with both the 1/V{sub max} and 2DSWML methods. We also assess a flux-limited sample to test the robustness of the methods applied to the full sample. These measurements are in excellent agreement with one another; the derived Schechter function parameters are {phi}{sub *} (h {sup 3}{sub 70} Mpc{sup -3} dex{sup -1}) = 4.8 {+-} 0.3 x 10{sup -3}, log (M{sub *}/M{sub sun}) + 2 log h{sub 70} = 9.96 {+-} 0.02, and {alpha} = -1.33 {+-} 0.02. We find {Omega}{sub H{sub i}}= 4.3 {+-} 0.3 x10{sup -4} h {sup -1}{sub 70}, 16% larger than the 2005 HIPASS result, and our Schechter function fit extrapolated to log (M{sub H{sub i}}/M{sub sun}) = 11.0 predicts an order of magnitude more galaxies than HIPASS. The larger values of {Omega}{sub H{sub i}} and of M{sub *} imply an upward adjustment for estimates of the detection rate of future large-scale H I line surveys with, e.g., the Square Kilometer Array. A comparison with simulated galaxies from the Millennium Run and a treatment of photoheating as a method of baryon removal from H I-selected halos indicate that the disagreement between dark matter mass functions and baryonic mass functions may soon be resolved.},
doi = {10.1088/0004-637X/723/2/1359},
url = {https://www.osti.gov/biblio/21471261}, journal = {Astrophysical Journal},
issn = {0004-637X},
number = 2,
volume = 723,
place = {United States},
year = {Wed Nov 10 00:00:00 EST 2010},
month = {Wed Nov 10 00:00:00 EST 2010}
}