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arXiv · 1901.11353

Intensive Monitoring Survey of Nearby Galaxies (IMSNG)

Myungshin Im·Changsu Choi·Sungyong Hwang·Gu Lim·Joonho Kim·Sophia Kim·Gregory S. H. Paek·Sang-Yun Lee·Sung-Chul Yoon·Hyunjin Jung·Hyun-Il Sung·Yeong-beom Jeon·Shuhrat Ehgamberdiev·Otabek Burhonov·Davron Milzaqulov·Omon Parmonov·Sang Gak Lee·Wonseok Kang·Taewoo Kim·Sun-gill Kwon·Soojong Pak·Tae-Geun Ji·Hye-In Lee·Woojin Park·Hojae Ahn·Seoyeon Byeon·Jimin Han·Coyne Gibson·J. Craig Wheeler·John Kuehne·Chris Johns-Krull·Jennifer Marshall·Minhee Hyun·Seong-Kook J. Lee·Yongjung Kim·Yongmin Yoon·Insu Paek·Suhyun Shin·Yoon Chan Taak·Juhyung Kang·Seoyeon Choi·Mankeun Jeong·Moo-Keon Jung·Hwara Kim·Jisu Kim·Dayae Lee·Bomi Park·Keunwoo Park·Seong A O
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Abstract

Intensive Monitoring Survey of Nearby Galaxies (IMSNG) is a high cadence observation program monitoring nearby galaxies with high probabilities of hosting supernovae (SNe). IMSNG aims to constrain the SN explosion mechanism by inferring sizes of SN progenitor systems through the detection of the shock-heated emission that lasts less than a few days after the SN explosion. To catch the signal, IMSNG utilizes a network of 0.5-m to 1-m class telescopes around the world and monitors the images of 60 nearby galaxies at distances D < 50 Mpc to a cadence as short as a few hours. The target galaxies are bright in near-ultraviolet (NUV) with M_NUV < -18.4 AB mag and have high probabilities of hosting SNe (0.06 SN/yr per galaxy). With this strategy, we expect to detect the early light curves of 3.4 SNe per year to a depth of R ~ 19.5 mag, enabling us to detect the shock-heated emission from a progenitor star with a radius as small as 0.1 R_sun. The accumulated data will be also useful for studying faint features around the target galaxies and other science projects. So far, 18 SNe have occurred in our target fields (16 in IMSNG galaxies) over 5 years, confirming our SN rate estimate of 0.06 SN/yr per galaxy.

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Myungshin Im, Changsu Choi, Sungyong Hwang, Gu Lim, Joonho Kim, Sophia Kim, Gregory S. H. Paek, Sang-Yun Lee, Sung-Chul Yoon, Hyunjin Jung, Hyun-Il Sung, Yeong-beom Jeon, Shuhrat Ehgamberdiev, Otabek Burhonov, Davron Milzaqulov, Omon Parmonov, Sang Gak Lee, Wonseok Kang, Taewoo Kim, Sun-gill Kwon, Soojong Pak, Tae-Geun Ji, Hye-In Lee, Woojin Park, Hojae Ahn, Seoyeon Byeon, Jimin Han, Coyne Gibson, J. Craig Wheeler, John Kuehne, Chris Johns-Krull, Jennifer Marshall, Minhee Hyun, Seong-Kook J. Lee, Yongjung Kim, Yongmin Yoon, Insu Paek, Suhyun Shin, Yoon Chan Taak, Juhyung Kang, Seoyeon Choi, Mankeun Jeong, Moo-Keon Jung, Hwara Kim, Jisu Kim, Dayae Lee, Bomi Park, Keunwoo Park, Seong A O. 2019-01-31. Intensive Monitoring Survey of Nearby Galaxies (IMSNG). https://doi.org/10.5303/jkas.2019.52.1.11

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