J/AJ/168/90 Galaxy pairs in the SDSS-DR17 photometric images (Shi+, 2024) ================================================================================ A survey of galaxy pairs in the SDSS photometric images based on faster-RCNN. Shi C.-H., Yang H.-F., Cai J.-H., Zhou L.-C., He Y.-T., Su M.-H., Zhao X.-J., Xun Y.-L. =2024AJ....168...90S ================================================================================ ADC_Keywords: Galaxies, interacting; Morphology; Redshifts; Surveys Keywords: Galaxy pairs ; Detection ; Astronomy data reduction ; Algorithms Abstract: Galaxy pairs hold significant importance in understanding the evolution of galaxies, and the extensive search for a large sample of galaxy pairs is meaningful. In this article, we develop a deep learning-based approach for the search of galaxy pairs and conduct a comprehensive search on Sloan Digital Sky Survey (SDSS) images. In nine million photometric images, 17965 physical galaxy pairs with spectral or photometric redshifts are detected. Four sets of results are provided, including physical pairs determined by two spectral redshifts, two photometric redshifts, one spectral redshift, and one photometric redshift, and visual irregular pairs that have no precise redshift information but can be inferred as physical galaxy pairs based on the morphological changes. Then their morphological and physical characteristics are explored, the redshifts of most targets are around 0.1, and as the redshift difference between two galaxies increases, the number of galaxy pairs gradually reduces. The distributions of star formation rate (SFR) are not the same for different morphologies of galaxy pairs, irregular pairs have higher SFR than the other three types, and statistics indicate that the SFR of galaxies depends on both nearby galaxies and internal properties. Color and stellar mass are also key properties of galaxies which can reflect the status of galaxy pairs. Compared to other surveys, a greater number of galaxy pair targets are detected, and this is also the first extensive detection of galaxy pairs in SDSS images using photometric redshifts. These galaxy pair samples can greatly aid in the study of galaxy evolution. File Summary: -------------------------------------------------------------------------------- FileName Lrecl Records Explanations -------------------------------------------------------------------------------- ReadMe 80 . This file table3.dat 135 8264 Physical galaxy pairs confirmed by spectral redshift table4.dat 73 4964 Physical galaxy pairs distinguished by photoz table5.dat 60 4737 Galaxy pairs with one spectral redshift and one photometric redshift table6.dat 19 38609 Visual irregular galaxy pairs -------------------------------------------------------------------------------- See also: VII/205 : Faint Interacting Galaxies (de Mello+ 1997) V/156 : LAMOST DR7 catalogs (Luo+, 2019) J/A+AS/110/371 : Southern binary galaxies. I. (Soares+, 1995) J/ApJ/511/595 : An X-Ray Survey of Galaxies in Pairs (Henriksen+, 1999) J/MNRAS/328/1181 : Extragalactic supernovae (Navasardyan+, 2001) J/ApJ/582/668 : Colors & H{alpha} in galaxy pairs (Barton Gillespie+, 2003) J/AJ/130/1516 : MCG pairs and triples of galaxies (De Propris+, 2005) J/AJ/129/682 : Structural data of S+S galaxies (Hernandez-Toledo+, 2005) J/A+A/456/467 : New sample of bright galaxy pairs in UZC (Focardi+, 2006) J/AJ/132/197 : Close pairs of galaxies (Woods+, 2006) J/MNRAS/388/1537 : Galaxy pairs from SDSS-DR2 (McIntosh+, 2008) J/AJ/139/1857 : Sample of major galaxy pairs at z=0.08-0.38 (Woods+, 2010) J/PASP/125/2 : Galaxy Zoo: overlapping galaxy pairs (Keel+, 2013) J/MNRAS/443/3528 : SDSS peculiar galaxy pairs list (Shamir+, 2014) J/MNRAS/444/2456 : Spectral galaxy pairs from SDSS DR9 (Yang+, 2014) J/A+A/578/A110 : Isolated gal., pairs and triplets (Argudo-Fernandez+, 2015) J/MNRAS/449/4277 : GAMA blended spectra catalogue (Holwerda+, 2015) J/other/AstBu/71.270 : The UGC isolated galaxy pair catalog (Chamaraux+, 2016) J/ApJ/829/78 : Dust data of major-merger galaxy pairs (Domingue+, 2016) J/MNRAS/465/588 : HI 21-cm absorption survey of QSO-gal. pairs (Dutta+, 2017) J/ApJ/856/93 : SDSS-IV MaNGA: kinematic galaxy pairs (Fu+, 2018) J/other/AstBu/73.310 : Isolated gal. pair limited to M<=-18.5 (Nottale+, 2018) J/A+A/611/A22 : Jekyll & Hyde galaxies ALMA cube & sp. (Schreiber+, 2018) J/ApJS/234/35 : Stellar pop. synthesis of clumps (Zaragoza-Cardiel+, 2018) J/A+A/630/A77 : Lyra system LoFAR and XMM images (Botteon+, 2019) J/A+A/631/A87 : Close pairs of galaxies in MUSE Deep Fields (Ventou+, 2019) J/ApJ/901/93 : Model atm. analysis of hot WDs from SDSSDR12 (Bedard+, 2020) J/ApJ/923/156 : Emission Line Galaxy Pairs from the WISP survey (Dai+, 2021) J/ApJ/909/120 : Close galaxy pairs and multiples in MaNGA (Steffen+, 2021) J/A+A/666/A97 : Early- & late-forming gal. cluster pair samples (Lin+, 2022) http://www.sdss.org/dr17/ : SDSS-DR17 home page http://www.lamost.org/lmusers/ : LAMOST data home page Byte-by-byte Description of file: table3.dat -------------------------------------------------------------------------------- Bytes Format Units Label Explanations -------------------------------------------------------------------------------- 1- 7 F7.3 deg RAdeg Right Ascension of galaxy 1 (J2000) 9- 15 F7.3 deg DEdeg [-11/68.4] Declination of galaxy 1 (J2000) 17- 23 F7.3 deg RA2deg Right Ascension of galaxy 2 (J2000) 25- 31 F7.3 deg DE2deg [-11/68.4] Declination of galaxy 2 (J2000) 33- 39 F7.5 --- z1 [0.0028/0.6] Spectroscopic redshift of galaxy 1 41- 47 F7.5 --- z2 [0.0028/0.6] Spectroscopic redshift of galaxy 2 49- 57 F9.5 km/s dv [0/240] Velocity difference between galaxies 1 and 2 59- 70 F12.9 [Msun] M1 [-3.71/3.9]? Log of stellar mass of galaxy 1 72- 83 F12.9 [Msun] M2 [-4.1/1.8]? Log of stellar mass of galaxy 2 85- 94 F10.7 --- M1/M2 [6.1/12.4]? Ratio of M1 to M2 96- 105 F10.7 [-] SFR1 [6/12]? Log of star formation rate of galaxy 1 107- 117 F11.5 [-] SFR2 [1/13952]? Log of star formation rate of galaxy 2 119- 120 I2 --- BPT1 [-1/5]? BPT class of galaxy 1 (1) 122- 123 I2 --- BPT2 [-1/5]? BPT class of galaxy 2 (1) 125 I1 --- MType [1/4] Morphological type of galaxy pair (2) 127- 129 A3 --- r_sp Sources of spectra (3) 131- 135 A5 --- isNew Indicates if target is newly discovered (4) -------------------------------------------------------------------------------- Note (1): Note as follows: -1 = unclassifiable; 1 = star-forming; 2 = low S/N star-forming; 3 = composite; 4 = AGN (excluding LINERs); 5 = low S/N LINER. Note (2): Note as follows: 1 = close pair (1713 occurrences) 2 = projection-separated pair (5039 occurrences) 3 = edge-on pair (698 occurrences) 4 = irregular pair (814 occurrences) Note (3): Note as follows: S+S = both spectra are from SDSS (2983 occurrences) S+L = one spectrum is from SDSS and the other is from LAMOST (2274 occurrences) L+L = both spectra are from LAMOST (3007 occurrences) Note (4): Note as follows: New = newly discovered (7156 occurrences) Known = not newly discovered -------------------------------------------------------------------------------- Byte-by-byte Description of file: table4.dat -------------------------------------------------------------------------------- Bytes Format Units Label Explanations -------------------------------------------------------------------------------- 1- 9 F9.5 deg RAdeg Right Ascension of galaxy 1 (J2000) 11- 19 F9.5 deg DEdeg [-23/84.6] Declination of galaxy 1 (J2000) 21- 29 F9.5 deg RA2deg Right Ascension of galaxy 2 (J2000) 31- 39 F9.5 deg DE2deg [-22.9/84.6] Declination of galaxy 2 (J2000) 41- 47 F7.5 --- z1 [0.012/0.8] Photometric redshift of galaxy 1 49- 55 F7.5 --- z2 [0.012/0.8] Photometric redshift of galaxy 2 57- 65 F9.5 km/s dv [0/240] Velocity difference between galaxies 1 and 2 67- 67 I1 --- MType [1/4] Morphological type of galaxy pair (1) 69- 73 A5 --- isNew Indicates if target is newly discovered (2) -------------------------------------------------------------------------------- Note (1): Note as follows: 1 = close pair (984 occurrences) 2 = projection-separated pair (3109 occurrences) 3 = edge-on pair (558 occurrences) 4 = irregular pair (313 occurrences) Note (2): Note as follows: New = newly discovered (4836 occurrences) Known = not newly discovered -------------------------------------------------------------------------------- Byte-by-byte Description of file: table5.dat -------------------------------------------------------------------------------- Bytes Format Units Label Explanations -------------------------------------------------------------------------------- 1- 7 F7.3 deg RAdeg Right Ascension of galaxy 1 (J2000) 9- 15 F7.3 deg DEdeg [-11.2/68.1] Declination of galaxy 1 (J2000) 17- 25 F9.5 deg RA2deg Right Ascension of galaxy 2 (J2000) 27- 35 F9.5 deg DE2deg [-11.2/68.1] Declination of galaxy 2 (J2000) 37- 43 F7.5 --- z1 [0.004/1] Spectroscopic redshift of galaxy 1 45- 51 F7.5 --- z2 [0.004/1] Photometric redshift of galaxy 2 53- 60 F8.4 km/s dv [0/240] Velocity difference between galaxies 1 and 2 -------------------------------------------------------------------------------- Byte-by-byte Description of file: table6.dat -------------------------------------------------------------------------------- Bytes Format Units Label Explanations -------------------------------------------------------------------------------- 1- 9 F9.5 deg RAdeg Right Ascension of galaxy pair center (J2000) 11- 19 F9.5 deg DEdeg [-23.7/85] Declination of galaxy pair center (J2000) -------------------------------------------------------------------------------- History: From electronic version of the journal ================================================================================ (End) Prepared by [AAS], Emmanuelle Perret [CDS] 19-May-2025