J/MNRAS/487/4901 HISS HI stacking tool applied to NIBLES spectra (Healy+, 2019)
HISS, a new tool for H I stacking: application to NIBLES spectra.
Healy J., Blyth S.-L., Elson E., van Driel W., Butcher Z., Schneider S.,
Lehnert M.D., Minchin R.
<Mon. Not. R. Astron. Soc., 487, 4901-4938 (2019)>
=2019MNRAS.487.4901H 2019MNRAS.487.4901H (SIMBAD/NED BibCode)
ADC_Keywords: Galaxies ; Radio lines ; Magnitudes ; Positional data ; H I data
Keywords: methods: data analysis - methods: statistical - galaxies: evolution -
galaxies: general - radio lines: galaxies
Abstract:
HI stacking has proven to be a highly effective tool to statistically
analyse average HI properties for samples of galaxies which may or may
not be directly detected. With the plethora of HI data expected from
the various upcoming HI surveys with the SKA Precursor and Pathfinder
telescopes, it will be helpful to standardize the way in which
stacking analyses are conducted. In this work we present a new
python-based package, HISS, designed to stack HI (emission and
absorption) spectra in a consistent and reliable manner. As an
example, we use HISS to study the HI content in various galaxy
sub-samples from the NIBLES survey of SDSS galaxies which were
selected to represent their entire range in total stellar mass without
a prior colour selection. This allowed us to compare the galaxy colour
to average HI content in both detected and non-detected galaxies. Our
sample, with a stellar mass range of 108<M*(M☉)<1012, has
enabled us to probe the HI-to-stellar mass gas fraction relationship
more than half an order of magnitude lower than in previous stacking
studies.
Description:
This work has detailed the development of a new 21cm HI spectral
stacking package in python (HI Stacking Software: HISS); while we have
exclusively used HI emission spectra to test HISS, it is capable of
stacking emission or absorption spectra of any characteristic line.
HISS takes the spectra for a sample of galaxies along with the
accompanying redshifts recorded in the galaxy catalogue to produce an
average spectrum from which a number of average properties (e.g. HI
mass, HI-to-stellar mass ratio) for the sample may be extracted.
We have applied hiss to stacking of 1000 HI spectra from the NIBLES,
which is a stellar mass-selected (with no colour-selection) HI survey
of SDSS galaxies in the nearby Universe (SDSS DR5; Adelman-McCarthy et
al. 2007ApJS..172..634A 2007ApJS..172..634A, Cat. II/276). Of the 1000 sources, 323 were
classified as non-detections (presented in Table E1) and 677 as
detections. Due to the wide stellar mass range spanned by the NIBLES
dataset (108<M*(M☉)<1012), extending an order of magnitude
lower than Brown et al. (2015MNRAS.452.2479B 2015MNRAS.452.2479B), we were able to extend
the previously studied gas fraction versus stellar mass gas scaling
relation (Fabello et al. 2011MNRAS.411..993F 2011MNRAS.411..993F; Catinella et al.
2013MNRAS.436...34C 2013MNRAS.436...34C, Cat. J/MNRAS/436/34; Brown et al.
2015MNRAS.452.2479B 2015MNRAS.452.2479B) down to lower average stellar mass
(<M*≥108.6M☉).
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
tablee1.dat 80 323 Data for the HI non-detections in the stacking
sample (updated version 21-03-2023)
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Byte-by-byte Description of file: tablee1.dat
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Bytes Format Units Label Explanations
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1- 4 I4 --- ID [1926/6759] Source identifier
6- 7 I2 h RAh Right ascension (J2000)
9- 10 I2 min RAm Right ascension (J2000)
12- 16 F5.2 s RAs Right ascension (J2000)
18 A1 --- DE- Declination sign (J2000)
19- 20 I2 deg DEd Declination (J2000)
22- 23 I2 arcmin DEm Declination (J2000)
25- 29 F5.2 arcsec DEs Declination (J2000)
31- 53 A23 --- Name Galaxy name
55- 59 I5 km/s Vopt Recession velocity (cz)
61- 62 I2 km/s e_Vopt Error on Vopt
64- 67 F4.2 mag u-r u-r color index
69- 74 F6.2 mag rMAG Absolute r-band magnitude
76- 80 F5.2 [Msun] logMass Logarithm of the galaxy's stellar mass
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History:
* 23-Jan-2023: From electronic version of the journal
* 21-Mar-2023: Positions corrected in tablee1.dat
(End) Ana Fiallos [CDS] 21-Nov-2022