J/A+A/574/A126 HeViCS. XVIII. Star-forming dwarf galaxies (Grossi+, 2015)
The Herschel Virgo Cluster Survey.
XVIII. Star-forming dwarf galaxies in a cluster environment.
Grossi M., Hunt L.K., Madden S.C., Hughes T.M., Auld R., Baes M.,
Bendo G.J., Bianchi S., Bizzocchi L., Boquien M., Boselli A., Clemens M.,
Corbelli E., Cortese L., Davies J., De Looze I., di Serego Alighieri S.,
Fritz J., Pappalardo C., Pierini D., Remy-Ruyer A., Smith M.W.L.,
Verstappen J., Viaene S., Vlahakis C.
<Astron. Astrophys., 574, A126-126 (2015)>
=2015A&A...574A.126G 2015A&A...574A.126G
ADC_Keywords: Clusters, galaxy ; Galaxy catalogs ;
Photometry, millimetric/submm ; Abundances
Keywords: galaxies: dwarf - galaxies: clusters: general - galaxies: ISM -
dust, extinction - infrared: ISM
Abstract:
To assess the effects of the cluster environment on the different
components of the interstellar medium, we analyse the far-infrared
(FIR) and submillimetre (submm) properties of a sample of star-forming
dwarf galaxies detected by the Herschel Virgo Cluster Survey (HeViCS).
We determine dust masses and dust temperatures by fitting a modified
black body function to the spectral energy distributions (SEDs).
Stellar and gas masses, star formation rates (SFRs), and metallicities
are obtained from the analysis of a set of ancillary data. Dust is
detected in 49 out of a total 140 optically identified dwarfs covered
by the HeViCS field; considering only dwarfs brighter than mB=18mag,
this gives a detection rate of 43%. After evaluating different
emissivity indices, we find that the FIR-submm SEDs are best-fit by
β=1.5, with a median dust temperature Td=22.4K. Assuming
β=1.5, 67% of the 23 galaxies detected in all five Herschel bands
show emission at 500µm in excess of the modified black-body model.
The fraction of galaxies with a submillimetre excess decreases for
lower values of β, while a similarly high fraction (54%) is found
if a β-free SED modelling is applied. The excess is inversely
correlated with SFR and stellar masses. To study the variations in the
global properties of our sample that come from environmental effects,
we compare the Virgo dwarfs to other Herschel surveys, such as the Key
Insights into Nearby Galaxies: Far-Infrared Survey with Herschel
(KINGFISH), the Dwarf Galaxy Survey (DGS), and the HeViCS Bright
Galaxy Catalogue (BGC). We explore the relations between stellar mass
and HI fraction, specific star formation rate, dust fraction,
gas-to-dust ratio over a wide range of stellar masses (from 107 to
1011M☉) for both dwarfs and spirals. Highly HI-deficient Virgo
dwarf galaxies are mostly characterised by quenched star formation
activity and lower dust fractions giving hints for dust stripping in
cluster dwarfs. However, to explain the large dust-to-gas mass ratios
observed in these systems, we find that the fraction of dust removed
has to be less than that of the HI component. The cluster environment
seems to mostly affect the gas component and star formation activity
of the dwarfs. Since the Virgo star-forming dwarfs are likely to be
crossing the cluster for the first time, a longer timescale might be
necessary to strip the more centrally concentrated dust distribution.
Description:
Herschel observations were carried out using the SPIRE/PACS parallel
scan-map mode with a fast scan speed of 60"/s over two orthogonal
crossed-linked scan directions. A total of 8 scans was then obtained
for each field, with overlapping regions between the four tiles being
covered by 16 scans.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 73 49 Stellar masses, HI and dust masses, SFR,
metallicities, HI deficiency and adopted distances
of star-forming dwarf galaxies detected by HeViCS
tablec1.dat 86 49 Herschel photometry of the sample of Virgo
star-forming dwarf galaxies
tablec2.dat 80 27 Stellar masses, HI and dust masses, SFR,
metallicities, HI deficiency, and distances of the
27 objects selected from the Dwarf Galaxy Survey
tablec3.dat 80 12 Stellar masses, HI and dust masses, SFR,
metallicities, HI deficiency, and distances of the
KINGFISH dwarf galaxy sample
tablec4.dat 96 39 Stellar masses, HI and dust masses, SFR,
H2 masses, HI deficiency and distances of
KINGFISH spiral galaxies (from Sa to Sd)
tablec5.dat 96 67 Stellar masses, HI and dust masses, SFR,
H2 masses, HI deficiency, and distances of
HeViCS BGC galaxies
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See also:
J/MNRAS/419/3505 : The HeViCS Bright Galaxy Sample (Davies+, 2012)
J/MNRAS/428/1880 : Far-IR properties of VCC galaxies (Auld+, 2013)
J/A+A/552/A8 : 454 VCC galaxies revised coordinates
(di Serego Alighieri+, 2013)
J/A+A/562/A106 : Planck submillimetre sources in Virgo Cluster (Baes+, 2014)
J/A+A/573/A129 : HeViCS. SPIRE point-source catalogs (Pappalardo+, 2015)
Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 3 A3 --- --- [VCC]
4- 7 I4 --- VCC [1/1791] VCC galaxy number
9- 12 F4.2 [Msun] logM* Stellar mass
14- 17 F4.2 [Msun] e_logM* rms uncertainty on logM*
19 A1 --- l_logMHI Limit flag on logMHI
20- 23 F4.2 [Msun] logMHI HI mass
25- 28 F4.2 [Msun] e_logMHI ? rms uncertainty on logMHI
30- 33 F4.2 [Msun] logMd Dust mass (G1)
34 A1 --- n_logMd [*] Fixed dust temperature (2)
36- 40 F5.2 [Msun/yr] logSFR ?=- Star formation rate
42- 45 F4.2 [Msun/yr] e_logSFR ? rms uncertainty on logSFR
46 A1 --- r_logSFR [abc] Reference for logSFR (3)
48- 51 F4.2 [-] Ab(O)P [8.0/8.9]?=- Abundance 12+log(O/H) from
Pilyugin & Thuan (2005ApJ...631..231P 2005ApJ...631..231P)
53- 56 F4.2 [-] e_Ab(O)P ? rms uncertainty on A(O)P
58- 61 F4.2 [-] Ab(O) [7.8/8.5]?=- Abundance 12+log(O/H)
63 A1 --- l_DefHI Limit flag on DefHI
64- 68 F5.2 [-] DefHI [-0.5/1.8] HI deficiency (G2)
70- 73 F4.1 Mpc Dist Adopted distance
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Note (2): Galaxies noted with (*) correspond to MBB fits with fixed dust
temperature, because of the lack of enough data points (see also Table 4).
Note (3): References for logSFR as follows:
a = SFR calculated from Eq. (4) (Wen et al., 2014MNRAS.438...97W 2014MNRAS.438...97W)
b = SFR calculated from Eq. (5) (Kennicutt & Evans, 2012ARA&A..50..531K 2012ARA&A..50..531K)
c = SFR calculated from Eq. (6) (Lee et al., 2009, Cat. J/ApJ/706/599)
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Byte-by-byte Description of file: tablec1.dat
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Bytes Format Units Label Explanations
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1- 3 A3 --- --- [VCC]
4- 7 I4 --- VCC [1/1791] VCC galaxy number
9 A1 --- l_F100 Limit flag on F100
10- 15 F6.3 Jy F100 Herschel/PACS 100µm flux density
17- 21 F5.3 Jy e_F100 ? rms uncertainty on F100
22 A1 --- n_F100 [+a*] Note on F100 (1)
24 A1 --- l_F160 Limit flag on F160
25- 30 F6.3 Jy F160 Herschel/PACS 160µm flux density
32- 36 F5.3 Jy e_F160 ? rms uncertainty on F160
37 A1 --- n_F160 [a] Note on F160 (1)
39- 43 F5.3 Jy F250 Herschel/SPIRE 250µm flux density
45- 49 F5.3 Jy e_F250 ? rms uncertainty on F250
51 A1 --- l_F350 Limit flag on F350
52- 56 F5.3 Jy F350 Herschel/SPIRE 350µm flux density
58- 62 F5.3 Jy e_F350 ? rms uncertainty on F350
64 A1 --- l_F500 Limit flag on F500
65- 69 F5.3 Jy F500 Herschel/SPIRE 500µm flux density
71- 75 F5.3 Jy e_F500 ? rms uncertainty on F500
76 A1 --- n_F500 [b] Note on F500 (1)
78- 81 F4.1 arcsec a25 Isophotal semi-major axis at B=25mag/arcsec2
83- 86 F4.1 arcsec b25 Isophotal semi-minor axis at B=25mag/arcsec2
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Note (1): Notes as follows:
a = Flux density from Cortese et al. (2014, Cat. J/MNRAS/440/942)
b = Time-line photometry from Pappalardo et al. (2015. Cat. J/A+A/573/A129)
+ = PACS 100um aperture size smaller by a factor ∼0.65 compared to other
Herschel bands
* = PACS 100um aperture size smaller by a factor ∼0.50 compared to other
Herschel bands
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Byte-by-byte Description of file: tablec2.dat tablec3.dat
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Bytes Format Units Label Explanations
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1- 11 A11 --- Name Galaxy name
13- 17 F5.2 [Msun] logM* ?=- Stellar mass
19- 22 F4.2 [Msun] e_logM* ? rms uncertainty on logM*
24 A1 --- l_logMHI Limit flag on logMHI
25- 29 F5.2 [Msun] logMHI ?=- HI mass
31- 34 F4.2 [Msun] e_logMHI ? rms uncertainty on logMHI
35 A1 --- r_logMHI [a] Reference for logMHI (1)
37- 40 F4.2 [Msun] logMd ?=- Dust mass (G1)
42- 45 F4.2 [Msun] e_logMd ? rms uncertainty on logMd
47- 51 F5.2 [Msun/yr] logSFR ?=- Star formation rate
53- 56 F4.2 [Msun/yr] e_logSFR ? rms uncertainty on logSFR
58- 61 F4.2 [-] Ab(O) [7.5/8.7]?=- Abundance 12+log(O/H)
63- 66 F4.2 [-] e_Ab(O) ? rms uncertainty on 12+log(O/H)
67 A1 --- r_Ab(O) [ac] Reference for 12+log(O/H) (1)
69- 73 F5.2 [-] DefHI ?=- HI deficiency (G2)
75- 79 F5.1 Mpc Dist Distance
80 A1 --- r_Dist [bc] Reference for Dist (1)
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Note (1): References as follows:
a = Remy-Ruyer et al. (2014A&A...563A..31R 2014A&A...563A..31R)
b = Madden et al. (2013PASP..125..600M 2013PASP..125..600M)
c = Kennicutt et al. (2011PASP..123.1347K 2011PASP..123.1347K)
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Byte-by-byte Description of file: tablec4.dat tablec5.dat
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Bytes Format Units Label Explanations
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1- 8 A8 --- Name Galaxy name
10- 14 F5.2 [Msun] logM* ?=- Stellar mass
16- 19 F4.2 [Msun] e_logM* ? rms uncertainty on logM*
21- 25 F5.2 [Msun] logMHI ?=- HI mass
27- 30 F4.2 [Msun] e_logMHI ? rms uncertainty on logMHI
31 A1 --- n_logMHI [ae] Reference for logMHI (1)
33- 36 F4.2 [Msun] logMd Dust mass (G1)
38- 41 F4.2 [Msun] E_logMd rms uncertainty on logMd
43- 46 F4.2 [Msun] e_logMd rms uncertainty on logMd
48- 52 F5.2 [Msun/yr] logSFR ?=- Star formation rate
54- 57 F4.2 [Msun/yr] e_logSFR ? rms uncertainty on logSFR
58 A1 ---- r_logSFR [d] Note on logSFR (1)
59 A1 --- l_logMH2MW Limit flag on logMH2MW
60- 64 F5.2 [Msun] logMH2MW ?=- H2 mass from MW conversion factor (2)
65 A1 --- r_logMH2MW [af] Reference for logMH2MW (1)
67 A1 --- l_logMH2Z Limit flag on logMH2MZ
68- 72 F5.2 [Msun] logMH2Z ?=- H2 mass from Z conversion factor (2)
73 A1 --- r_logMH2Z [af] Reference for logMH2Z (1)
75- 78 F4.2 [-] Ab(O) [8.1/8.8]?=- Abundance 12+log(O/H)
80- 83 F4.2 [-] e_Ab(O) ? rms uncertainty on 12+log(O/H)
84 A1 --- r_Ab(O) [cg] Reference for 12+log(O/H) (1)
86- 90 F5.2 [-] DefHI HI deficiency (G2)
92- 95 F4.1 Mpc Dist Distance
96 A1 --- r_Dist [ce] Reference for Dist (1)
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Note (1): References as follows:
a = Remy-Ruyer et al. (2014A&A...563A..31R 2014A&A...563A..31R)
c = Kennicutt et al. (2011PASP..123.1347K 2011PASP..123.1347K).
e = GOLDMine (Gavazzi et al. 2003A&A...400..451G 2003A&A...400..451G, 2014, 1401.8123)
f = Boselli et al. (2014, Cat. J/A+A/564/A65)
g = Hughes et al. (2013, Cat. J/A+A/550/A115)
Note (2): H2 masses computed with (see Remy-Ruyer et al. 2014A&A...563A..31R 2014A&A...563A..31R)
MW = galactic (Milky Way) CO to H2 conversion factor
Z = CO to H2 conversion factor that depends on the metallicity
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Global notes:
Note (G1): Dust masses were determined fitting a single Modified Black Body
(MBB: S(ν,T)∝κν.B(ν,T), with the opacity
κν∝(ν/ν0)β) with a fixed β=1.5
emissivity from 100 to 350µm.
Note (G2): the HI deficiency is defined as the logarithmic difference
between the HI mass of a reference sample of isolated galaxies for a
given morphological type: DefHI=log(MHIref/logMHIobs)
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History:
From electronic version of the journal
References:
Davies et al., Paper I 2010A&A...518L..48D 2010A&A...518L..48D
Cortese et al., Paper II 2010A&A...518L..49C 2010A&A...518L..49C
Clemens et al., Paper III 2010A&A...518L..50C 2010A&A...518L..50C
Smith et al., Paper IV 2010A&A...518L..51S 2010A&A...518L..51S
Grossi et al., Paper V 2010A&A...518L..52G 2010A&A...518L..52G
baes et al., Paper VI 2010A&A...518L..53B 2010A&A...518L..53B
De Looze et al., Paper VII 2010A&A...518L..54D 2010A&A...518L..54D
Davies et al. Paper VIII 2012MNRAS.419.3505D 2012MNRAS.419.3505D, J/MNRAS/419/3505
Magrini et al., Paper IX 2011A&A...535A..13M 2011A&A...535A..13M
Corbelli et al., Paper X 2012A&A...542A..32C 2012A&A...542A..32C
Pappalardo et al., Paper XI 2012A&A...545A..75P 2012A&A...545A..75P
Auld et al., Paper XII 2013MNRAS.428.1880A 2013MNRAS.428.1880A, J/MNRAS/428/1880
di Serego Alighieri et al., Paper XIII 2013A&A...552A...8D 2013A&A...552A...8D, J/A+A/552/A8
De Looze et al., Paper XIV 2013MNRAS.436.1057D 2013MNRAS.436.1057D
Baes et al., Paper XV 2014A&A...562A.106B 2014A&A...562A.106B, J/A+A/562/A106
Davies et al. Paper XVI 2014MNRAS.438.1922D 2014MNRAS.438.1922D
Pappalardo et al., Paper XVII 2015A&A...573A.129P 2015A&A...573A.129P, J/A+A/573/A129
(End) Patricia Vannier [CDS] 09-Mar-2015