_version_ 1866911188637450240
author Sakai, Nobuyuki
Poshyachinda, Saran
Sugiyama, Koichiro
Rujopakarn, Wiphu
Soonthornthum, Boonrucksar
Leckngam, Apichat
Kramer, Busaba
Jaroenjittichai, Phrudth
Pimpanuwat, Bannawit
Singwong, Dan
Kanjana, Kitipoom
Prasert, Nikom
Punyawarin, Songklod
Sarris, Spiro
Chairin, Teep
Bandudej, Kamorn
Nuchur, Chalunthon
Sani, Haseng
Chanwedchasart, Nattawit
Chatuphot, Pathit
Jiraya, Prachayapan
Sathipjan, Saharat
Eakwan, Adirake
Larkaew, Chayanin
Naewchan, Settasak
Pha-Kham, Pichate
Duangbuppha, Siritida
Chaichana, Thodsawat
Bunwong, Attapon
Doomcome, Panupan
Poonnawatt, Anya
Noisapung, Warakorn
Sathapornvajana, Pathorn
Yawilerng, Naphat
Dilokthanakul, Thita
Angkaew, Kritsada
Chaiwongwan, Nattawut
Khanchaiyapoom, Jittimat
Kobayashi, Hideyuki
Chen, Yu-An
Intrarat, Nawamin
Wieching, Gundolf
Barr, Ewan
Wu, Jason
Esser, Niclas
Winchen, Tobias
Vicente, Pablo
author_facet Sakai, Nobuyuki
Poshyachinda, Saran
Sugiyama, Koichiro
Rujopakarn, Wiphu
Soonthornthum, Boonrucksar
Leckngam, Apichat
Kramer, Busaba
Jaroenjittichai, Phrudth
Pimpanuwat, Bannawit
Singwong, Dan
Kanjana, Kitipoom
Prasert, Nikom
Punyawarin, Songklod
Sarris, Spiro
Chairin, Teep
Bandudej, Kamorn
Nuchur, Chalunthon
Sani, Haseng
Chanwedchasart, Nattawit
Chatuphot, Pathit
Jiraya, Prachayapan
Sathipjan, Saharat
Eakwan, Adirake
Larkaew, Chayanin
Naewchan, Settasak
Pha-Kham, Pichate
Duangbuppha, Siritida
Chaichana, Thodsawat
Bunwong, Attapon
Doomcome, Panupan
Poonnawatt, Anya
Noisapung, Warakorn
Sathapornvajana, Pathorn
Yawilerng, Naphat
Dilokthanakul, Thita
Angkaew, Kritsada
Chaiwongwan, Nattawut
Khanchaiyapoom, Jittimat
Kobayashi, Hideyuki
Chen, Yu-An
Intrarat, Nawamin
Wieching, Gundolf
Barr, Ewan
Wu, Jason
Esser, Niclas
Winchen, Tobias
Vicente, Pablo
contents Although the optical cometary database is extensive, the radio database is limited. The 18-cm OH maser observations of comets allow us to determine (i) the production rate of OH ($Q_{\rm{OH}}$) and (ii) the water expansion velocity, for each comet. To reveal the physical properties of the periodic comet 12P/Pons-Brooks, we conducted the OH maser observations of the comet using the 40-m TNRT (Thai National Radio Telescope) on March 22nd, 27th and 29th, 2024 before the perihelion passage on April 21st, 2024. We successfully detected 1665 and 1667 MHz OH maser emissions from the comet. The average OH production rates of 12P/Pons-Brooks were determined as 4.28$\pm$0.30 $\times$ 10$^{29}$ sec$^{-1}$, 5.21$\pm$0.42 $\times$ 10$^{29}$ sec$^{-1}$, and 3.36$\pm$0.43 $\times$ 10$^{29}$ sec$^{-1}$ for March 22nd, 27th and 29th, respectively. Combining our results with previous estimates, we find that the OH production rate of 12P/Pons-Brooks shows some fluctuations on timescales of a few days, but gradually increases on longer timescales as the comet approaches the last perihelion. The water expansion velocities of the comet were determined to be 1.55$\pm$0.14 km s$^{-1}$, 1.55$\pm$0.35 km s$^{-1}$, and 2.02$^{+0.47}_{-0.45}$ km s$^{-1}$ for the observations on March 22nd, 27th and 29th, respectively. The reason why the errors are different is because the signal to noise ratio is different for each OH maser emission. All expansion velocities are consistent with the individual results of the heuristic law (Tseng et al. 2007) within errors.
format Preprint
id arxiv_https___arxiv_org_abs_2510_01373
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle Detection of OH maser emission in the 71-year periodic comet 12P/Pons-Brooks using the 40-m Thai National Radio Telescope (TNRT)
Sakai, Nobuyuki
Poshyachinda, Saran
Sugiyama, Koichiro
Rujopakarn, Wiphu
Soonthornthum, Boonrucksar
Leckngam, Apichat
Kramer, Busaba
Jaroenjittichai, Phrudth
Pimpanuwat, Bannawit
Singwong, Dan
Kanjana, Kitipoom
Prasert, Nikom
Punyawarin, Songklod
Sarris, Spiro
Chairin, Teep
Bandudej, Kamorn
Nuchur, Chalunthon
Sani, Haseng
Chanwedchasart, Nattawit
Chatuphot, Pathit
Jiraya, Prachayapan
Sathipjan, Saharat
Eakwan, Adirake
Larkaew, Chayanin
Naewchan, Settasak
Pha-Kham, Pichate
Duangbuppha, Siritida
Chaichana, Thodsawat
Bunwong, Attapon
Doomcome, Panupan
Poonnawatt, Anya
Noisapung, Warakorn
Sathapornvajana, Pathorn
Yawilerng, Naphat
Dilokthanakul, Thita
Angkaew, Kritsada
Chaiwongwan, Nattawut
Khanchaiyapoom, Jittimat
Kobayashi, Hideyuki
Chen, Yu-An
Intrarat, Nawamin
Wieching, Gundolf
Barr, Ewan
Wu, Jason
Esser, Niclas
Winchen, Tobias
Vicente, Pablo
Earth and Planetary Astrophysics
Astrophysics of Galaxies
Although the optical cometary database is extensive, the radio database is limited. The 18-cm OH maser observations of comets allow us to determine (i) the production rate of OH ($Q_{\rm{OH}}$) and (ii) the water expansion velocity, for each comet. To reveal the physical properties of the periodic comet 12P/Pons-Brooks, we conducted the OH maser observations of the comet using the 40-m TNRT (Thai National Radio Telescope) on March 22nd, 27th and 29th, 2024 before the perihelion passage on April 21st, 2024. We successfully detected 1665 and 1667 MHz OH maser emissions from the comet. The average OH production rates of 12P/Pons-Brooks were determined as 4.28$\pm$0.30 $\times$ 10$^{29}$ sec$^{-1}$, 5.21$\pm$0.42 $\times$ 10$^{29}$ sec$^{-1}$, and 3.36$\pm$0.43 $\times$ 10$^{29}$ sec$^{-1}$ for March 22nd, 27th and 29th, respectively. Combining our results with previous estimates, we find that the OH production rate of 12P/Pons-Brooks shows some fluctuations on timescales of a few days, but gradually increases on longer timescales as the comet approaches the last perihelion. The water expansion velocities of the comet were determined to be 1.55$\pm$0.14 km s$^{-1}$, 1.55$\pm$0.35 km s$^{-1}$, and 2.02$^{+0.47}_{-0.45}$ km s$^{-1}$ for the observations on March 22nd, 27th and 29th, respectively. The reason why the errors are different is because the signal to noise ratio is different for each OH maser emission. All expansion velocities are consistent with the individual results of the heuristic law (Tseng et al. 2007) within errors.
title Detection of OH maser emission in the 71-year periodic comet 12P/Pons-Brooks using the 40-m Thai National Radio Telescope (TNRT)
topic Earth and Planetary Astrophysics
Astrophysics of Galaxies
url https://arxiv.org/abs/2510.01373