J/ApJ/604/141 Hα fluxes in Cl J0023+0423B galaxies (Finn+, 2004)
Hα-derived star formation rates for the z=0.84 galaxy cluster
Cl J0023+0423B.
Finn R.A., Zaritsky D., Mccarthy D.W.Jr
<Astrophys. J., 604, 141-152 (2004)>
=2004ApJ...604..141F 2004ApJ...604..141F
ADC_Keywords: Clusters, galaxy ; Redshifts ; Equivalent widths
Keywords: galaxies: clusters: individual (Cl J0023+0423B) -
galaxies: evolution - galaxies: high-redshift - stars: formation
Abstract:
We present Hα-derived star formation rates (SFRs) for the galaxy
cluster Cl J0023+0423B at z=0.845. Our 3σ flux limits correspond
to an SFR of 0.24h100-2M☉/yr, and our minimum reliable
Hα+[NII] equivalent width is greater than 10Å, demonstrating
that near-infrared narrow-band imaging can sample the star-forming
galaxy population in distant clusters. Comparison with spectroscopy
shows that the number of false detections is low (9%±6%) and that
our Hα equivalent widths are correlated with spectroscopically
determined [O II] equivalent widths. A magnitude-limited spectroscopic
survey conducted over the same area missed 70% of the star-forming
galaxies and 65% of the integrated star formation. Using Hubble Space
Telescope Wide Field Planetary Camera 2 Archive images, we fit Sersic
profiles to all galaxies with significant narrow-band equivalent widths
and find that equivalent width decreases as the steepness of galaxy
profile increases.
Description:
We observed Cl J0023+0423B using the PISCES near-infrared camera at
the 6.5m MMT on 2002 December 19 equipped with a standard J continuum
narrow-band filter (λc=1.208µm).
Objects:
-----------------------------------------
RA (2000) DE Designation(s)
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00 23 52 +04 23.1 ClG J0023+0423
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 123 94 Data for CL J0023+0423B galaxies
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See also:
J/AJ/116/560 : Cl J0023+0423 and Cl J1604+4304 spectroscopy (Postman+ 1998)
J/AJ/116/584 : Cl J0023+0423 and Cl J1604+4304 morphology (Lubin+ 1998)
Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 2 I2 --- [FZM2004] Object designation
4- 8 F5.1 arcsec oRA Right Ascension offset from BCG
10- 14 F5.1 arcsec oDE Declination offset from BCG
16- 20 F5.1 pix Xpos X pixel coordinates (1)
22- 26 F5.1 pix Ypos Y pixel coordinates (1)
28- 31 F4.1 s-1 FNar Narrow-band flux, in units of ADU/s
33- 35 F3.1 s-1 e_FNar Uncertainty in FNar
37- 41 F5.1 s-1 FJ The J band flux, in units of ADU/s
43- 45 F3.1 s-1 e_FJ Uncertainty in FJ
47- 50 F4.1 s-1 FCS Continuum-subtracted flux,
in units of ADU/s
52- 54 F3.1 s-1 e_FCS Uncertainty in FCS
56- 60 F5.1 0.1nm EWNar Narrow-band equivalent width in Angstroms
62- 66 F5.1 0.1nm e_EWNar Uncertainty in EWNar
68- 73 F6.2 10-20W/m2 FHa Hα flux in 10-17ergs/s/cm2
75- 78 F4.2 10-20W/m2 e_FHa Uncertainty in FHa
80- 83 F4.1 10+34W LHa Hαluminosity in 1041erg/s
85- 87 F3.1 10+34W e_LHa Uncertainty in LHa
89- 92 F4.1 solMass/yr SFR Star formation rate in h1002M☉/yr
94- 96 F3.1 solMass/yr e_SFR Uncertainty in SFR
98-100 I3 --- MDS ? Lubin et al. name (1998 Cat. J/AJ/116/584)
[OPL98] MDS J0023+0423 NNN in Simbad
102-107 F6.4 --- z ? Redshift from Postman et al. (1998,
Cat. J/AJ/116/560)
109-112 F4.1 --- TType ? Morphological type from Lubin et al.
(1998, Cat. J/AJ/116/584) (2)
114-118 F5.2 --- n ? Sersic index
120-123 F4.2 --- e_n ? Uncertainty in n
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Note (1): 1 pix = 0.18". East is up, North is right.
Note (2):
Where E = 0, S0 = 0.1, Sa = 1, Sb = 3, Sc = 5, Sd = 7, Sm/Im = 9,
Peculiar = 10. We denote galaxies that Lubin et al. (1998, Cat.
J/AJ/116/584) classify as extremely compact with a T-type of -1
and peculiar with 10.
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History:
From electronic version of the journal
(End) Greg Schwarz [AAS], Patricia Vannier [CDS] 07-May-2004