J/AJ/135/1624 PEARS emission-line galaxies (Straughn+, 2008)
Emission-line galaxies from the PEARS Hubble ultra deep field:
a 2D detection method and first results.
Straughn A.N., Meurer G.R., Pirzkal N., Cohen S.H., Malhotra S., Rhoads J.,
Windhorst R.A., Gardner J.P., Hathi N.P., Xu C., Gronwall C.,
Koekemoer A.M., Walsh J., Alighieri S.D.S.
<Astron. J., 135, 1624-1635 (2008)>
=2008AJ....135.1624S 2008AJ....135.1624S
ADC_Keywords: Galaxies, spectra ; Photometry, SDSS ; Redshifts
Keywords: galaxies: starburst - methods: data analysis -
techniques: spectroscopic
Abstract:
The Hubble Space Telescope Advanced Camera for Surveys grism Probing
Evolution And Reionization Spectroscopically (PEARS) survey provides a
large dataset of low-resolution spectra from thousands of galaxies in
the GOODS north and south fields. One important subset of objects in
these data is emission-line galaxies (ELGs), and we have investigated
several different methods aimed at systematically selecting these
galaxies. Here, we present a new methodology and results of a search
for these ELGs in the PEARS observations of the Hubble Ultra Deep
Field (HUDF) using a 2D detection method that utilizes the observation
that many emission lines originate from clumpy knots within galaxies.
This 2D line-finding method proves to be useful in detecting emission
lines from compact knots within galaxies that might not otherwise be
detected using more traditional 1D line-finding techniques.
Description:
The PEARS ACS grism survey data consist of eight ACS fields with three
HST roll angles each (with limiting AB magnitude i'AB≲26.5mag; 20
HST orbits per field) plus the HUDF field with four roll angles
(limiting AB magnitude i'AB~<27.5mag; 40 HST orbits total) taken with
the ACS WFC G800L grism. The G800L grism yields low-resolution (R∼100)
optical spectroscopy between 6000-9500Å. Four PEARS fields were
observed in the GOODS-N and five fields (including the HUDF) in the
GOODS-S. A forthcoming data paper (S. Malhotra et al. 2008, in
preparation) will describe the PEARS project and data in detail.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 75 95 Global properties of emission-line galaxies
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See also:
J/ApJ/653/1004 : Galaxies at 1.4≲z≲3.0 in GOODS-North Field (Reddy+, 2006)
J/ApJ/689/687 : GOODS-N spectroscopic survey (Barger+, 2008)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 5 I5 --- PEARS PEARS identification number
7- 8 I2 --- Knot Knot number
10- 19 F10.7 deg RAdeg Right ascension in decimal degrees (J2000)
21- 31 F11.7 deg DEdeg Declination in decimal degrees (J2000)
33- 37 F5.2 mag i'mag ?=- ACS i' magnitude in AB system
(HST/ACS F775W) (1)
39- 42 I4 0.1nm lambda Wavelength (Å)
44- 48 F5.1 zW/m2 Flux ?=- Flux at wavelength (in 10-18erg/cm2/s
= 10-21W/m2) (1)
50- 53 F4.1 zW/m2 e_Flux ? rms uncertainty on Flux
55- 60 F6.1 0.1nm EW ?=- Equivalent width at wavelength (1)
63- 70 A8 --- Line Line ID (2)
71- 75 F5.3 --- z ?=- Re-calculated redshift based on the
line identification (1)
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Note (1): No data indicates measurement was not possible.
Note (2): Blank indicates line could not be identified.
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History:
From electronic version of the journal
(End) Patricia Vannier [CDS] 06-Nov-2010