_version_ 1866910835299844096
author Pucha, Ragadeepika
Juneau, S.
Dey, Arjun
Siudek, M.
Mezcua, M.
Moustakas, J.
BenZvi, S.
Hainline, K.
Hviding, R.
Mao, Yao-Yuan
Alexander, D. M.
Alfarsy, R.
Circosta, C.
Guo, Wei-Jian
Manwadkar, V.
Martini, P.
Weaver, B. A.
Aguilar, J.
Ahlen, S.
Bianchi, D.
Brooks, D.
Canning, R.
Claybaugh, T.
Dawson, K.
de la Macorra, A.
Dey, Biprateep
Doel, P.
Font-Ribera, A.
Forero-Romero, J. E.
Gaztañaga, E.
Gontcho, S. Gontcho A
Gutierrez, G.
Honscheid, K.
Kehoe, R.
Koposov, S. E.
Lambert, A.
Landriau, M.
Guillou, L. Le
Meisner, A.
Miquel, R.
Prada, F.
Rossi, G.
Sanchez, E.
Schlegel, D.
Schubnell, M.
Seo, H.
Sprayberry, D.
Tarlé, G.
Zou, H.
author_facet Pucha, Ragadeepika
Juneau, S.
Dey, Arjun
Siudek, M.
Mezcua, M.
Moustakas, J.
BenZvi, S.
Hainline, K.
Hviding, R.
Mao, Yao-Yuan
Alexander, D. M.
Alfarsy, R.
Circosta, C.
Guo, Wei-Jian
Manwadkar, V.
Martini, P.
Weaver, B. A.
Aguilar, J.
Ahlen, S.
Bianchi, D.
Brooks, D.
Canning, R.
Claybaugh, T.
Dawson, K.
de la Macorra, A.
Dey, Biprateep
Doel, P.
Font-Ribera, A.
Forero-Romero, J. E.
Gaztañaga, E.
Gontcho, S. Gontcho A
Gutierrez, G.
Honscheid, K.
Kehoe, R.
Koposov, S. E.
Lambert, A.
Landriau, M.
Guillou, L. Le
Meisner, A.
Miquel, R.
Prada, F.
Rossi, G.
Sanchez, E.
Schlegel, D.
Schubnell, M.
Seo, H.
Sprayberry, D.
Tarlé, G.
Zou, H.
contents Using early data from the Dark Energy Spectroscopic Instrument (DESI) survey, we search for AGN signatures in 410,757 line-emitting galaxies. By employing the BPT emission-line ratio diagnostic diagram, we identify AGN in 75,928/296,261 ($\approx$25.6%) high-mass ($\log (M_{\star}/\rm M_{\odot}) >$ 9.5) and 2,444/114,496 ($\approx$2.1%) dwarf ($\log (M_{\star}/\rm M_{\odot}) \leq$ 9.5) galaxies. Of these AGN candidates, 4,181 sources exhibit a broad H$α$ component, allowing us to estimate their BH masses via virial techniques. This study more than triples the census of dwarf AGN and doubles the number of intermediate-mass black hole (IMBH; $M_{BH} \le 10^6~\rm M_{\odot}$) candidates, spanning a broad discovery space in stellar mass (7 $< \log (M_{\star}/M_{\odot}) <$ 12) and redshift (0.001 $< \rm z <$ 0.45). The observed AGN fraction in dwarf galaxies ($\approx$2.1%) is nearly four times higher than prior estimates, primarily due to DESI's smaller fiber size, which enables the detection of lower luminosity dwarf AGN candidates. We also extend the $M_{BH} - M_{\star}$ scaling relation down to $\log (M_{\star}/M_{\odot}) \approx$ 8.5 and $\log (M_{BH}/\rm M_{\odot}) \approx$ 4.4, with our results aligning well with previous low-redshift studies. The large statistical sample of dwarf AGN candidates from current and future DESI releases will be invaluable for enhancing our understanding of galaxy evolution at the low-mass end of the galaxy mass function.
format Preprint
id arxiv_https___arxiv_org_abs_2411_00091
institution arXiv
publishDate 2024
record_format arxiv
spellingShingle Tripling the Census of Dwarf AGN Candidates Using DESI Early Data
Pucha, Ragadeepika
Juneau, S.
Dey, Arjun
Siudek, M.
Mezcua, M.
Moustakas, J.
BenZvi, S.
Hainline, K.
Hviding, R.
Mao, Yao-Yuan
Alexander, D. M.
Alfarsy, R.
Circosta, C.
Guo, Wei-Jian
Manwadkar, V.
Martini, P.
Weaver, B. A.
Aguilar, J.
Ahlen, S.
Bianchi, D.
Brooks, D.
Canning, R.
Claybaugh, T.
Dawson, K.
de la Macorra, A.
Dey, Biprateep
Doel, P.
Font-Ribera, A.
Forero-Romero, J. E.
Gaztañaga, E.
Gontcho, S. Gontcho A
Gutierrez, G.
Honscheid, K.
Kehoe, R.
Koposov, S. E.
Lambert, A.
Landriau, M.
Guillou, L. Le
Meisner, A.
Miquel, R.
Prada, F.
Rossi, G.
Sanchez, E.
Schlegel, D.
Schubnell, M.
Seo, H.
Sprayberry, D.
Tarlé, G.
Zou, H.
Astrophysics of Galaxies
Using early data from the Dark Energy Spectroscopic Instrument (DESI) survey, we search for AGN signatures in 410,757 line-emitting galaxies. By employing the BPT emission-line ratio diagnostic diagram, we identify AGN in 75,928/296,261 ($\approx$25.6%) high-mass ($\log (M_{\star}/\rm M_{\odot}) >$ 9.5) and 2,444/114,496 ($\approx$2.1%) dwarf ($\log (M_{\star}/\rm M_{\odot}) \leq$ 9.5) galaxies. Of these AGN candidates, 4,181 sources exhibit a broad H$α$ component, allowing us to estimate their BH masses via virial techniques. This study more than triples the census of dwarf AGN and doubles the number of intermediate-mass black hole (IMBH; $M_{BH} \le 10^6~\rm M_{\odot}$) candidates, spanning a broad discovery space in stellar mass (7 $< \log (M_{\star}/M_{\odot}) <$ 12) and redshift (0.001 $< \rm z <$ 0.45). The observed AGN fraction in dwarf galaxies ($\approx$2.1%) is nearly four times higher than prior estimates, primarily due to DESI's smaller fiber size, which enables the detection of lower luminosity dwarf AGN candidates. We also extend the $M_{BH} - M_{\star}$ scaling relation down to $\log (M_{\star}/M_{\odot}) \approx$ 8.5 and $\log (M_{BH}/\rm M_{\odot}) \approx$ 4.4, with our results aligning well with previous low-redshift studies. The large statistical sample of dwarf AGN candidates from current and future DESI releases will be invaluable for enhancing our understanding of galaxy evolution at the low-mass end of the galaxy mass function.
title Tripling the Census of Dwarf AGN Candidates Using DESI Early Data
topic Astrophysics of Galaxies
url https://arxiv.org/abs/2411.00091