_version_ 1866913540080664576
author Lan, Ting-Wen
Prochaska, J. Xavier
Moustakas, John
Siudek, Małgorzata
Aguilar, J.
Ahlen, S.
Bianchi, D.
Brooks, D.
Claybaugh, T.
Cole, S.
Dawson, K.
de la Macorra, A.
Doel, P.
Forero-Romero, J. E.
Gaztañaga, E.
Gontcho, S. Gontcho A
Gutierrez, G.
Guy, J.
Honscheid, K.
Kehoe, R.
Kisner, T.
Lambert, A.
Landriau, M.
Meisner, A.
Miquel, R.
Muñoz-Gutiérrez, A.
Newman, J. A.
Poppett, C.
Prada, F.
Rossi, G.
Sanchez, E.
Schubnell, M.
Seo, H.
Sprayberry, D.
Tarlé, G.
Weaver, B. A.
Zou, H.
author_facet Lan, Ting-Wen
Prochaska, J. Xavier
Moustakas, John
Siudek, Małgorzata
Aguilar, J.
Ahlen, S.
Bianchi, D.
Brooks, D.
Claybaugh, T.
Cole, S.
Dawson, K.
de la Macorra, A.
Doel, P.
Forero-Romero, J. E.
Gaztañaga, E.
Gontcho, S. Gontcho A
Gutierrez, G.
Guy, J.
Honscheid, K.
Kehoe, R.
Kisner, T.
Lambert, A.
Landriau, M.
Meisner, A.
Miquel, R.
Muñoz-Gutiérrez, A.
Newman, J. A.
Poppett, C.
Prada, F.
Rossi, G.
Sanchez, E.
Schubnell, M.
Seo, H.
Sprayberry, D.
Tarlé, G.
Weaver, B. A.
Zou, H.
contents We study the [OII] profiles of emission line galaxies (ELGs) from the Early Data Release of the Dark Energy Spectroscopic Instrument (DESI). To this end, we decompose and classify the shape of [OII] profiles with the first two eigenspectra derived from Principal Component Analysis. Our results show that DESI ELGs have diverse line profiles which can be categorized into three main types: (1) narrow lines with a median width of ~50 km/s, (2) broad lines with a median width of ~80 km/s, and (3) two-redshift systems with a median velocity separation of ~150 km/s, i.e., double-peak galaxies. To investigate the connections between the line profiles and galaxy properties, we utilize the information from the COSMOS dataset and compare the properties of ELGs, including star-formation rate (SFR) and galaxy morphology, with the average properties of reference star-forming galaxies with similar stellar mass, sizes, and redshifts. Our findings show that on average, DESI ELGs have higher SFR and more asymmetrical/disturbed morphology than the reference galaxies. Moreover, we uncover a relationship between the line profiles, the excess SFR and the excess asymmetry parameter, showing that DESI ELGs with broader [OII] line profiles have more disturbed morphology and higher SFR than the reference star-forming galaxies. Finally, we discuss possible physical mechanisms giving rise to the observed relationship and the implications of our findings on the galaxy clustering measurements, including the halo occupation distribution modeling of DESI ELGs and the observed excess velocity dispersion of the satellite ELGs.
format Preprint
id arxiv_https___arxiv_org_abs_2410_07601
institution arXiv
publishDate 2024
record_format arxiv
spellingShingle DESI Emission Line Galaxies: Unveiling the Diversity of [OII] Profiles and its Links to Star Formation and Morphology
Lan, Ting-Wen
Prochaska, J. Xavier
Moustakas, John
Siudek, Małgorzata
Aguilar, J.
Ahlen, S.
Bianchi, D.
Brooks, D.
Claybaugh, T.
Cole, S.
Dawson, K.
de la Macorra, A.
Doel, P.
Forero-Romero, J. E.
Gaztañaga, E.
Gontcho, S. Gontcho A
Gutierrez, G.
Guy, J.
Honscheid, K.
Kehoe, R.
Kisner, T.
Lambert, A.
Landriau, M.
Meisner, A.
Miquel, R.
Muñoz-Gutiérrez, A.
Newman, J. A.
Poppett, C.
Prada, F.
Rossi, G.
Sanchez, E.
Schubnell, M.
Seo, H.
Sprayberry, D.
Tarlé, G.
Weaver, B. A.
Zou, H.
Astrophysics of Galaxies
We study the [OII] profiles of emission line galaxies (ELGs) from the Early Data Release of the Dark Energy Spectroscopic Instrument (DESI). To this end, we decompose and classify the shape of [OII] profiles with the first two eigenspectra derived from Principal Component Analysis. Our results show that DESI ELGs have diverse line profiles which can be categorized into three main types: (1) narrow lines with a median width of ~50 km/s, (2) broad lines with a median width of ~80 km/s, and (3) two-redshift systems with a median velocity separation of ~150 km/s, i.e., double-peak galaxies. To investigate the connections between the line profiles and galaxy properties, we utilize the information from the COSMOS dataset and compare the properties of ELGs, including star-formation rate (SFR) and galaxy morphology, with the average properties of reference star-forming galaxies with similar stellar mass, sizes, and redshifts. Our findings show that on average, DESI ELGs have higher SFR and more asymmetrical/disturbed morphology than the reference galaxies. Moreover, we uncover a relationship between the line profiles, the excess SFR and the excess asymmetry parameter, showing that DESI ELGs with broader [OII] line profiles have more disturbed morphology and higher SFR than the reference star-forming galaxies. Finally, we discuss possible physical mechanisms giving rise to the observed relationship and the implications of our findings on the galaxy clustering measurements, including the halo occupation distribution modeling of DESI ELGs and the observed excess velocity dispersion of the satellite ELGs.
title DESI Emission Line Galaxies: Unveiling the Diversity of [OII] Profiles and its Links to Star Formation and Morphology
topic Astrophysics of Galaxies
url https://arxiv.org/abs/2410.07601