J/ApJ/923/156 Emission Line Galaxy Pairs from the WISP survey (Dai+, 2021)
Spectroscopically identified emission line galaxy pairs in the WISP survey.
Dai Y.S., Malkan M.M., Teplitz H.I., Scarlata C., Alavi A., Atek H.,
Bagley M., Baronchelli I., Battisti A., Bunker A.J., Hathi N.P., Henry A.,
Huang J., Jin G., Li Z., Martin C., Mehta V., Phillips J., Rafelski M.,
Rutkowski M., Xu H., Xu C.K., Zanella A.
<Astrophys. J., 923, 156 (2021)>
=2021ApJ...923..156D 2021ApJ...923..156D
ADC_Keywords: Galaxies, spectra; Galaxies, interacting; Redshifts;
Spectra, infrared; Surveys
Keywords: Galaxy evolution ; Galaxy pairs ; Galaxy interactions ;
Extragalactic astronomy ; Interacting galaxies ;
High-redshift galaxies ; Galaxy spectroscopy
Abstract:
We identify a sample of spectroscopically measured emission line
galaxy (ELG) Pairs up to z=1.6 from the Wide Field Camera 3 (WFC3)
Infrared Spectroscopic Parallels (WISP) survey. WISP obtained
slitless, near-infrared grism spectroscopy along with direct imaging
in the J and H bands by observing in the pure-parallel mode with the
WFC3 on board the Hubble Space Telescope. From our search of 419 WISP
fields covering an area of ∼0.5deg2, we find 413 ELG pair systems,
mostly Hα emitters. We then derive reliable star formation rates
(SFRs) based on the attenuation-corrected Hα fluxes. Compared to
isolated galaxies, we find an average SFR enhancement of 40%-65%,
which is stronger for major Pairs and Pairs with smaller velocity
separations (Δv<300km/s). Based on the stacked spectra from
various subsamples, we study the trends of emission line ratios in
pairs, and find a general consistency with enhanced lower ionization
lines. We study the pair fraction among ELGs, and find a marginally
significant increase with redshift f∝(1+z)α, where the
power-law index α=0.58±0.17 from z∼0.2 to ∼1.6. The fraction
of active galactic nuclei is found to be the same in the ELG Pairs as
compared to the isolated ELGs.
Description:
The sample of emission line galaxy (ELG) Pairs was selected from the
Wide Field Camera 3 (WFC3) Infrared Spectroscopic Parallels (WISP)
survey. WISP obtained slitless, near-infrared grism spectroscopy along
with direct imaging in the J and H bands, by observing in the
pure-parallel mode with the WFC3 on board HST over ∼1000 orbits. The
spectra are obtained with the G102 (λ=0.8-1.15um, R∼210) and
G141 grisms ((λ=1.075-1.70um, R∼130), together with direct
imaging in the J and JH or H bands (F110W and F140W/F160W, respectively).
A total of 413 spectroscopically identified ELG pair systems are
selected from a parent sample of 8192 ELGs in 419 WISP fields.
See Section 2.2.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 77 413 Emission line galaxy pair sample
table2.dat 109 413 Galaxy properties of the emission line galaxy pair
sample
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See also:
J/ApJ/617/240 : Oxygen abundances in the GOODS-N field (Kobulnicky+, 2004)
J/ApJ/685/235 : Host and companion galaxies in the SDSS (Patton+, 2008)
J/ApJ/697/1369 : GOODS Ks-selected multiwavelength compilation (Bundy+, 2009)
J/MNRAS/489/2792 : Clumps and satellites impact on galaxy mass (Zanella+, 2019)
http://wisps.ipac.caltech.edu/ : WFC3 IR Spectroscopic Parallel Survey home
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 16 A16 --- WISP WISP pair identifier (FFF-NNN_FFF-NNNNN)
18- 27 F10.6 deg RAdeg Primary Right Ascension (J2000)
29- 38 F10.6 deg DEdeg [-72.2/65.2] Primary Declination (J2000)
40- 49 F10.6 deg RASdeg Secondary Right Ascension (J2000)
51- 60 F10.6 deg DESdeg [-72.2/65.2] Secondary Declination (J2000)
62- 69 F8.5 arcsec Sep [0.28/28] Separation between primary and secondary
71- 77 F7.3 km/s DeltaV [0/998] Comoving velocity offset (G1)
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Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 16 A16 --- WISP WISP identifier (FFF-NNN_FFF-NNNNN)
18- 24 F7.5 --- zP [0.27/2.34] Spectroscopic redshift for
primary (G1)
26- 32 F7.5 --- zS [0.27/2.34] Spectroscopic redshift for
secondary (G1)
34 I1 --- Filt [0/1]? HST filter flag (1)
36- 40 F5.2 mag HmagP [18.79/]?=99 Apparent H band AB magnitude for
primary
42- 46 F5.2 mag HmagS [19.63/]?=99 Apparent H band AB magnitude for
secondary
48- 55 E8.2 10-7W FHaP [1.6e-17/3.3e-15]? Hα line flux for
primary (2)
57- 64 E8.2 10-7W e_FHaP [5.5e-18/2.3e-16]? Uncertainty in FHaP
66- 73 E8.2 10-7W FHaS [1.3e-17/1.2e-15]? Hα line flux for
secondary (2)
75- 82 E8.2 10-7W e_FHaS [3e-18/1.6e-16]? Uncertainty in FHaS
84- 90 F7.2 Msun/yr SFRP [0.78/3166]? Star formation rate for primary
(3)
92- 96 F5.2 Msun/yr e_SFRP [0.09/17.3]? Uncertainty in SFRP
98- 104 F7.2 Msun/yr SFRS [0/487]? Star formation rate for secondary (3)
106- 109 F4.2 Msun/yr e_SFRS [0/9.7]? Uncertainty in SFRS
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Note (1): HST filter flag as follows:
0 = HST/WFPC3 default F160 filter (308 occurrences);
1 = HST/WFPC3 F140 filter (105 occurrences).
Note (2): With the [NII] lines removed (see Section 2.4). In units of erg/s.
Note (3): With the [NII] lines removed, dust corrected (see Section 3),
and Salpeter IMF.
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Global notes:
Note (G1): The typical redshift uncertainty is ∼0.1%
(Colbert+ 2013ApJ...779...34C 2013ApJ...779...34C), which translates to a velocity
uncertainty of ∼70-200km/s, depending on the actual redshift of the
pair members.
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History:
From electronic version of the journal
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 19-May-2023