J/ApJ/949/72 Star-forming clumps in 6 jellyfish gal. from HST (Giunchi+, 2023)
HST imaging of star-forming clumps in six GASP ram-pressure-stripped galaxies.
Giunchi E., Gullieuszik M., Poggianti B.M., Moretti A., Werle A.,
Scarlata C., Zanella A., Vulcani B., Calzetti D.
<Astrophys. J., 949, 72 (2023)>
=2023ApJ...949...72G 2023ApJ...949...72G
ADC_Keywords: Clusters, galaxy; Galaxies, optical; Galaxies, spectra; Redshifts;
Velocity dispersion; Star Forming Region; Photometry, HST;
Ultraviolet
Keywords: Galaxy clusters ; Galaxy evolution ; Star formation ;
Star forming regions ; Galaxy structure ; Galaxy tails
Abstract:
Exploiting broad- and narrowband images of the Hubble Space Telescope
from the near-UV to I-band rest frame, we study the star-forming
clumps of six galaxies of the GASP sample undergoing strong ram
pressure stripping. Clumps are detected in Hα and near-UV,
tracing star formation on different timescales. We consider clumps
located in galaxy disks and stripped tails and formed in stripped gas
but still close to the disk, called extraplanar. We detect
2406 Hα-selected clumps (1708 in disks, 375 in extraplanar
regions, and 323 in tails) and 3745 UV-selected clumps (2021 disk,
825 extraplanar, and 899 tail clumps). Only ∼15% of star-forming
clumps are spatially resolved, meaning that most are smaller than
∼140pc. We study the luminosity and size distribution functions (LDFs
and SDFs, respectively) and the luminosity-size relation. The average
LDF slope is 1.79±0.09, while the average SDF slope is 3.1±0.5.
The results suggest that the star formation is turbulence-driven and
scale-free, as in main-sequence galaxies. All of the clumps, whether
they are in the disks or tails, have an enhanced Hα luminosity
at a given size, compared to the clumps in main-sequence galaxies.
Indeed, their Hα luminosity is closer to that of clumps in
starburst galaxies, indicating that ram pressure is able to enhance
the luminosity. No striking differences are found among disk and tail
clumps, suggesting that the different environments in which they are
embedded play a minor role in influencing the star formation.
Description:
In this work, we focus on the study of the luminosities and sizes of
the star-forming clumps and complexes in a subsample of six GAs
Stripping Phenomena in galaxies with MUSE (GASP;
Poggianti+ 2017ApJ...844...48P 2017ApJ...844...48P) ESO Large Program galaxies whose main
properties are listed in Table 1.
The galaxies were observed using the WFC3/UVIS on board HST using four
broadband filters (F275W, F336W, F606W, and F814W) that cover a
spectral range from the UV to I-band rest frame. In addition, galaxies
were also observed with a narrowband filter, F680N, in order to
collect the Hα emission at the redshift of these galaxies.
Details of the observations, data reduction, calibration and analysis,
estimate of the standard deviation of the background in each band
(σ), and Hα+[NII] extraction from the F680N band are
described in Gullieuszik+ 2023ApJ...945...54G 2023ApJ...945...54G ; See Section 2.1.
Throughout this work, we also exploit the information obtained from
the GASP survey to remove regions powered by active galactic nuclei
(AGN) or shocks using BPT maps, confirm the redshift of star-forming
clump candidates, and correct the F680N filter for the line emission
of NII. All galaxies were observed in service mode with MUSE.
MUSE spectra cover a spectral range from 4500 to 9300Å sampled at
∼1.25Å/pixel and with a spectral resolution of 2.6Å.
See Section 2.2.
File Summary:
--------------------------------------------------------------------------------
FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
table1.dat 127 6 Summary of the main properties of the galaxies
studied in this paper and their host clusters
tablea3.dat 295 6252 Catalog of Hα- and UV-selected clump
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See also:
J/ApJS/132/37 : Spectroscopy of Southern warm IR galaxies (Kewley+, 2001)
J/A+A/495/707 : WINGS spectroscopy of 48 galaxy clusters (Cava+, 2009)
J/ApJ/735/75 : HST observations of HII regions in M51 (Lee+, 2011)
J/MNRAS/452/3508 : Young stellar structures in NGC 6503 (Gouliermis+, 2015)
J/MNRAS/462/3766 : List of galaxies with star forming regions (Cook+, 2016)
J/AJ/151/78 : Jellyfish galaxy cand. in galaxy clusters (Poggianti+, 2016)
J/A+A/607/A81 : Properties of the sample of clusters (Biviano+, 2017)
J/ApJ/895/106 : GAs Stripping Phenomena with MUSE (Franchetto+, 2020)
J/ApJ/899/13 : GASP. XXI. Star forming rate in 54 gal. (Gullieuszik+, 2020)
J/A+A/640/A22 : Jellyfish galaxy JO201 JVLA datacube (Ramatsoku+, 2020)
J/ApJ/907/22 : GASP. XXXII. Diffuse Ionized Gas (DIG) data (Tomicic+, 2021)
J/A+A/658/A188 : PHANGS-MUSE sample HII regions catalog (Santoro+, 2022)
Byte-by-byte Description of file: table1.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 5 A5 --- Gal Galaxy identifier (1)
7- 8 I2 h RAh Galaxy Hour of right ascension (J2000)
10- 11 I2 min RAm Minute of right ascension (J2000)
13- 18 F6.3 s RAs Second of right ascension (J2000)
20 A1 --- DE- Galaxy Sign of declination (J2000)
21- 22 I2 deg DEd Galaxy Degree of declination (J2000)
24- 25 I2 arcmin DEm Arcminute of declination (J2000)
27- 31 F5.2 arcsec DEs Arcsecond of declination (J2000)
33- 36 F4.1 10+10Msun Ms [3.2/29] Galaxy stellar mass from
Vulcani+ 2018ApJ...866L..25V 2018ApJ...866L..25V
38- 41 F4.1 10+10Msun e_Ms [2.4/22] Lower uncertainty on Ms
43- 46 F4.1 10+10Msun E_Ms [3.7/36] Upper uncertainty on Ms
48- 52 F5.3 --- Ha/Ha+NII [0.53/0.71] Median value for Hα to
Hα+[NII] ratio (2)
54- 59 F6.4 --- zGal [0.04/0.07] Redshift of the galaxy
61- 67 A7 --- Cluster Host cluster name
69- 71 I3 km/s sigma [575/859] Cluster velocity dispersion (3)
73- 75 I3 km/s e_sigma [-49/-31]? Lower uncertainty on sigma
77- 79 I3 km/s E_sigma [33/53]? Upper uncertainty on sigma
81- 86 F6.4 --- zCluster [0.04/0.07] Cluster redshift (3)
88- 127 A40 --- Ref References (4)
--------------------------------------------------------------------------------
Note (1): GASP ID of the galaxy as in Poggianti+ 2016, J/AJ/151/78
Note (2): Median value for Hα/(Hα+[NII]) from the MUSE clumps
listed in Poggianti+ 2019MNRAS.482.4466P 2019MNRAS.482.4466P
Note (3): Cluster redshifts and velocity dispersions are taken from
Cava+ 2009, J/A+A/495/707 and Biviano+ 2017, J/A+A/607/A81
Note (4): References as follows:
1 = Poggianti et al. 2017ApJ...844...48P 2017ApJ...844...48P
2 = Gullieuszik et al. 2017ApJ...846...27G 2017ApJ...846...27G
3 = Bellhouse et al. 2017ApJ...844...49B 2017ApJ...844...49B
4 = Poggianti et al. 2017Natur.548..304P 2017Natur.548..304P
5 = George et al. 2018MNRAS.479.4126G 2018MNRAS.479.4126G
6 = Moretti et al. 2018MNRAS.480.2508M 2018MNRAS.480.2508M
7 = Poggianti et al. 2019MNRAS.482.4466P 2019MNRAS.482.4466P
8 = Bellhouse et al. 2019MNRAS.485.1157B 2019MNRAS.485.1157B
9 = George et al. 2019MNRAS.487.3102G 2019MNRAS.487.3102G
10 = Radovich et al. 2019MNRAS.486..486R 2019MNRAS.486..486R
11 = Moretti et al. 2020ApJ...889....9M 2020ApJ...889....9M
12 = Deb et al. 2020MNRAS.494.5029D 2020MNRAS.494.5029D
13 = Ramatsoku et al. 2020, J/A+A/640/A22
14 = Bellhouse et al. 2021MNRAS.500.1285B 2021MNRAS.500.1285B
15 = Tomicic et al. 2021, J/ApJ/907/22
16 = Campitiello et al. 2021ApJ...911..144C 2021ApJ...911..144C
17 = Ignesti et al. 2022ApJ...924...64I 2022ApJ...924...64I
18 = Tomicic et al. 2021ApJ...922..131T 2021ApJ...922..131T
19 = Ignesti et al. 2022ApJ...937...58I 2022ApJ...937...58I
20 = Sun et al. 2022NatAs...6..270S 2022NatAs...6..270S
21 = Peluso et al. 2022ApJ...927..130P 2022ApJ...927..130P
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Byte-by-byte Description of file: tablea3.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 2 A2 --- Set Selection Filter (1)
4- 21 A18 --- Clump Clump identifier (id_clump) (2)
23- 27 A5 --- Gal Galaxy identifier (2)
29 A1 --- Run [ABC] Astrodendro Run (id_catalog) (2)(3)
31- 34 I4 --- idx [0/1763] Identifier number
(in Selection Filter) (2)
36- 54 F19.15 deg RAdeg [10.3/354.2] Right Ascension (J2000)
56- 75 F20.16 deg DEdeg [-53/21.2] Declination (J2000)
77- 83 A7 --- x_Lum Unit for Lum (4)
85- 94 E10.4 --- Lum Luminosity (4)
96- 105 E10.4 --- e_Lum [9.7e+34/8.4e+38] Uncertainty in Lum (4)
107- 113 F7.4 arcsec2 Area [0.008/11.5] Area (area_exact)
115- 120 F6.4 arcsec amaj [0.02/1.5] Semi-major axis (major_sigma)
122- 127 F6.4 arcsec bmin [0.01/0.8] Semi-minor axis (minor_sigma)
129- 137 F9.4 deg PA [-180/180] Position Angle, east of north
(position_angle)
139- 144 F6.4 arcsec rcore [0.018/1.1] Core radius
146- 151 F6.4 kpc rcore-c [0/0.98] PSF-corrected core radius
(rcore,corr)
153- 163 E11.4 cW/m2/nm F275W [-7.83e-20/4.03e-16] HST/WFC3 F275W Flux
Density, erg/Angstrom/s/cm2
165- 174 E10.4 cW/m2/nm e_F275W [1.8e-20/1.1e-18] Uncertainty in F275W
176- 186 E11.4 cW/m2/nm F336W HST/WFC3 F336W Flux Density,
erg.Angstrom-1.s-1.cm-2
188- 197 E10.4 cW/m2/nm e_F336W Uncertainty in F336W
199- 209 E11.4 cW/m2/nm F606W HST/WFC3 F606W Flux Density,
erg.Angstrom-1.s-1.cm-2
211- 220 E10.4 cW/m2/nm e_F606W Uncertainty in F606W
222- 232 E11.4 cW/m2/nm F680N HST/WFC3 F680N Flux Density,
erg.Angstrom-1.s-1.cm-2
234- 243 E10.4 cW/m2/nm e_F680N Uncertainty in F680N
245- 255 E11.4 cW/m2/nm F814W [-9.5e-21/5.92e-16] HST/WFC3 F814W Flux
Density, erg.Angstrom-1.s-1.cm-2
257- 266 E10.4 cW/m2/nm e_F814W [3e-21/3.31e-19] Uncertainty in F814W
268- 278 E11.4 mW/m2 F680Ncont [-1.2e-16/1.4e-13] Continuum-subtracted
F680N line flux, erg/s/cm2
280- 289 E10.4 mW/m2 e_F680Ncont [2.5e-18/1.71e-16] Uncertainty in F680N
291 I1 --- Dendro [0/3]? Position of clump in tree hierarchy
(dendro_flag) (5)
293 I1 --- Tail [0/2]? Spatial category of the clump
(tailgalflag) (6)
295 I1 --- BPT [0/4]? BPT category (BPT_flag) (7)
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Note (1): Set as follows:
ha = Hα selected clumps (2439 occurrences)
uv = UV-selected clumps in the F275W (3813 occurrences)
See Section 4.2.
Note (2): Each clump is univocally determined by the name of the
galaxy (gal), the Astrodendro run (Run), and an ID number (idx),
which is specific to the selection category (ha or uv).
Note (3): Astrodendro Run -- See the Appendix.
Note (4): Luminosity in the selection filter, not corrected for dust,
but corrected for NII in the case of Hα-selected clumps.
Hα luminosity is in erg/s and corrected to remove NII emission,
while UV luminosity is in erg/s/Å.
Note (5): Flag for the clump properties in the tree structure as follows:
0 = trunks which are not leaves (100 occurrences)
1 = trunks which are also leaves (5218 occurrences)
2 = branches (101 occurrences)
3 = leaves which are not trunks (833 occurrences)
Note (6): Flag for the spatial category as follows:
0 = tail (1224 occurrences)
1 = extraplanar (1209 occurrences)
2 = disk (3819 occurrences)
Note (7): Flag for the BPT classification as follows:
0 = no BPT diagram available (778 occurrences)
1 = star-forming (3444 occurrences)
2 = composite (1227 occurrences)
3 = AGN (457 occurrences)
4 = LINER (346 occurrences)
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History:
From electronic version of the journal
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 11-Jul-2025