Huan-Yu Teng, Bun’ei Sato, Masayuki Kuzuhara, Takuya Takarada, Masashi Omiya, Hiroki Harakawa, Hideyuki Izumiura, Eiji Kambe, Mesut Yilmaz, Ilfan Bikmaev, Selim O Selam, Timothy D Brandt, Guang-Yao Xiao, Michitoshi Yoshida, Yoichi Itoh, Hiroyasu Ando, Eiichiro Kokubo, Shigeru Ida
Abstract In this study, we revisit 32 planetary systems around evolved stars observed within the framework of the Okayama Planet Search Program (OPSP) and its collaborative framework of the East Asian Planet Search Network to search for additional companions and investigate the properties of stars and giant planets in multiple-planet systems. With our latest radial velocities obtained from Okayama Astrophysical Observatory, we confirm an additional giant planet in the wide orbit of the 75 Cet system ($P_{rm {c}} = 2051.62_{-40.47}^{+45.98} rm {d}$, $M_{rm {c}}sin i=0.912_{-0.090}^{+0.088},,M_{rm {J}}$, and $a_{rm {c}}=3.929_{-0.058}^{+0.052} rm {au}$), along with five stars exhibiting long-term radial velocity accelerations, which indicates massive companions in the wide orbits. We also find that the radial velocity variations of several planet-harboring stars may indicate additional planet candidates, stellar activities, or other understudied sources. These stars include ϵ Tau, 11 Com, 24 Boo, 41 Lyn, 14 And, HD 32518, and ω Ser. We further constrain the orbital configuration of the HD 5608, HD 14067, HD 120084, and HD 175679 systems by combining radial velocities with astrometry, as their host central stars exhibit significant astrometric accelerations. For other systems, we simply refine their orbital parameters. Moreover, our study indicates that the OPSP planet-harboring stars are more metal poor compared to the currently known planet-harboring stars, and this is likely due to the B − V color upper limit at 1.0 for star selection in the beginning of the survey. Finally, by investigating the less massive giant planets (<5 MJ) around currently known planet-harboring evolved stars, we find that metallicity positively correlates with the multiplicity and total planet mass of the system, which can be evidence for the core-accretion planet formation model.
{"title":"Revisiting planetary systems in the Okayama Planet Search Program: A new long-period planet, RV astrometry joint analysis, and a multiplicity-metallicity trend around evolved stars","authors":"Huan-Yu Teng, Bun’ei Sato, Masayuki Kuzuhara, Takuya Takarada, Masashi Omiya, Hiroki Harakawa, Hideyuki Izumiura, Eiji Kambe, Mesut Yilmaz, Ilfan Bikmaev, Selim O Selam, Timothy D Brandt, Guang-Yao Xiao, Michitoshi Yoshida, Yoichi Itoh, Hiroyasu Ando, Eiichiro Kokubo, Shigeru Ida","doi":"10.1093/pasj/psad056","DOIUrl":"https://doi.org/10.1093/pasj/psad056","url":null,"abstract":"Abstract In this study, we revisit 32 planetary systems around evolved stars observed within the framework of the Okayama Planet Search Program (OPSP) and its collaborative framework of the East Asian Planet Search Network to search for additional companions and investigate the properties of stars and giant planets in multiple-planet systems. With our latest radial velocities obtained from Okayama Astrophysical Observatory, we confirm an additional giant planet in the wide orbit of the 75 Cet system ($P_{rm {c}} = 2051.62_{-40.47}^{+45.98} rm {d}$, $M_{rm {c}}sin i=0.912_{-0.090}^{+0.088},,M_{rm {J}}$, and $a_{rm {c}}=3.929_{-0.058}^{+0.052} rm {au}$), along with five stars exhibiting long-term radial velocity accelerations, which indicates massive companions in the wide orbits. We also find that the radial velocity variations of several planet-harboring stars may indicate additional planet candidates, stellar activities, or other understudied sources. These stars include ϵ Tau, 11 Com, 24 Boo, 41 Lyn, 14 And, HD 32518, and ω Ser. We further constrain the orbital configuration of the HD 5608, HD 14067, HD 120084, and HD 175679 systems by combining radial velocities with astrometry, as their host central stars exhibit significant astrometric accelerations. For other systems, we simply refine their orbital parameters. Moreover, our study indicates that the OPSP planet-harboring stars are more metal poor compared to the currently known planet-harboring stars, and this is likely due to the B − V color upper limit at 1.0 for star selection in the beginning of the survey. Finally, by investigating the less massive giant planets (&lt;5 MJ) around currently known planet-harboring evolved stars, we find that metallicity positively correlates with the multiplicity and total planet mass of the system, which can be evidence for the core-accretion planet formation model.","PeriodicalId":20733,"journal":{"name":"Publications of the Astronomical Society of Japan","volume":"48 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135690047","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract The X-ray spectral state transitions of Galactic black hole transients (GBHTs) are often linked to the changes in the mass accretion rate. A narrow distribution of transition luminosity in terms of the Eddington ratio has been found in previous studies of GBHTs based on RXTE data (Maccarone, 2003, A&A, 409, 697; Vahdat Motlagh et al., 2019, MNRAS, 485, 2744) and this Eddington ratio at the transition is often used in recent studies with instruments such as Swift/XRT and NICER/XTI, covering soft energies below 1 to 10 keV. However, the X-ray states characterized by spectral parameters may have different definitions depending on the energy ranges adopted in the spectral analysis, leaving the question of whether the distribution of transition luminosity obtained with RXTE remains the same when we use the instruments covering softer energy bands. In this work, we investigated the X-ray state evolutions and the variations of luminosities of eight outbursts of seven GBHTs. We found that the bolometric luminosity of the power-law component was tightly constrained to $sim! 1.3%$ Eddington luminosity at index transition when the photon index starts to decrease towards the hard state, which is consistent with the previous RXTE results (Vahdat Motlagh et al. 2019, MNRAS, 485, 2744; Kalemci et al. 2013, ApJ, 779, 95). Moreover, the tightest clustering was found to be the power-law luminosity right after the start of disk recession, with a mean logarithmic Eddington ratio of −1.84 ± 0.28. In addition, our results suggest that the disk recession starts after the bolometric disk luminosity drops below 1% Eddington luminosity.
银河系黑洞瞬态(GBHTs)的x射线光谱状态跃迁通常与质量吸积速率的变化有关。先前基于RXTE数据的GBHTs研究发现，从Eddington比值来看，过渡光度的分布很窄(macarone, 2003, A&A, 409,697;Vahdat Motlagh et al.， 2019, MNRAS, 485, 2744)，在最近的研究中，经常使用Swift/XRT和NICER/XTI等仪器，覆盖1至10 keV以下的软能量。然而，根据光谱分析中所采用的能量范围，光谱参数表征的x射线状态可能有不同的定义，这就留下了一个问题，即当我们使用覆盖较软能带的仪器时，RXTE获得的跃迁光度分布是否保持不变。在这项工作中，我们研究了7个gbht的8次爆发的x射线状态演变和光度变化。我们发现幂律分量的热光度被严格限制在$sim!1.3%$ Eddington在光子指数开始向硬态下降时的指数跃迁光度，这与之前的RXTE结果一致(Vahdat Motlagh et al. 2019, MNRAS, 485, 2744;Kalemci et al. 2013, ApJ, 779, 95)。此外，发现最紧密的聚类是在盘衰退开始后的幂律光度，其平均对数Eddington比为- 1.84±0.28。此外，我们的研究结果表明，盘的衰退开始于热光度低于1%爱丁顿光度的时候。
{"title":"Transition luminosities of Galactic black hole transients with Swift/XRT and NICER/XTI observations","authors":"Sili Wang, Nobuyuki Kawai, Megumi Shidatsu, Yoshiki Matsuoka","doi":"10.1093/pasj/psad057","DOIUrl":"https://doi.org/10.1093/pasj/psad057","url":null,"abstract":"Abstract The X-ray spectral state transitions of Galactic black hole transients (GBHTs) are often linked to the changes in the mass accretion rate. A narrow distribution of transition luminosity in terms of the Eddington ratio has been found in previous studies of GBHTs based on RXTE data (Maccarone, 2003, A&A, 409, 697; Vahdat Motlagh et al., 2019, MNRAS, 485, 2744) and this Eddington ratio at the transition is often used in recent studies with instruments such as Swift/XRT and NICER/XTI, covering soft energies below 1 to 10 keV. However, the X-ray states characterized by spectral parameters may have different definitions depending on the energy ranges adopted in the spectral analysis, leaving the question of whether the distribution of transition luminosity obtained with RXTE remains the same when we use the instruments covering softer energy bands. In this work, we investigated the X-ray state evolutions and the variations of luminosities of eight outbursts of seven GBHTs. We found that the bolometric luminosity of the power-law component was tightly constrained to $sim! 1.3%$ Eddington luminosity at index transition when the photon index starts to decrease towards the hard state, which is consistent with the previous RXTE results (Vahdat Motlagh et al. 2019, MNRAS, 485, 2744; Kalemci et al. 2013, ApJ, 779, 95). Moreover, the tightest clustering was found to be the power-law luminosity right after the start of disk recession, with a mean logarithmic Eddington ratio of −1.84 ± 0.28. In addition, our results suggest that the disk recession starts after the bolometric disk luminosity drops below 1% Eddington luminosity.","PeriodicalId":20733,"journal":{"name":"Publications of the Astronomical Society of Japan","volume":"48 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135982378","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Tenri Jinno, Takayuki R Saitoh, Yota Ishigaki, Junichiro Makino
Abstract In the conventional theory of planet formation, it is assumed that protoplanetary disks are axisymmetric and have a smooth radial profile. However, recent radio observations of protoplanetary disks have revealed that many of them have complex radial structures. In this study, we perform a series of N-body simulations to investigate how planets are formed in protoplanetary disks with radial structures. For this purpose, we consider the effect of continuous pebble accretion onto the discontinuity boundary within the terrestrial planet-forming region (∼0.6 au). We find that protoplanets grow efficiently at the discontinuity boundary, reaching the Earth mass within ∼104 yr. We confirm that giant collisions of protoplanets occur universally in our model. Moreover, we find that multiple planet-sized bodies form at regular intervals in the vicinity of the discontinuity boundary. These results indicate the possibility of the formation of solar system-like planetary systems in radially structured protoplanetary disks.
{"title":"<i>N</i>-body simulation of planetary formation through pebble accretion in a radially structured protoplanetary disk","authors":"Tenri Jinno, Takayuki R Saitoh, Yota Ishigaki, Junichiro Makino","doi":"10.1093/pasj/psad053","DOIUrl":"https://doi.org/10.1093/pasj/psad053","url":null,"abstract":"Abstract In the conventional theory of planet formation, it is assumed that protoplanetary disks are axisymmetric and have a smooth radial profile. However, recent radio observations of protoplanetary disks have revealed that many of them have complex radial structures. In this study, we perform a series of N-body simulations to investigate how planets are formed in protoplanetary disks with radial structures. For this purpose, we consider the effect of continuous pebble accretion onto the discontinuity boundary within the terrestrial planet-forming region (∼0.6 au). We find that protoplanets grow efficiently at the discontinuity boundary, reaching the Earth mass within ∼104 yr. We confirm that giant collisions of protoplanets occur universally in our model. Moreover, we find that multiple planet-sized bodies form at regular intervals in the vicinity of the discontinuity boundary. These results indicate the possibility of the formation of solar system-like planetary systems in radially structured protoplanetary disks.","PeriodicalId":20733,"journal":{"name":"Publications of the Astronomical Society of Japan","volume":"35 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135048159","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Rei Enokiya, Hidetoshi Sano, Miroslav D Filipović, Rami Z E Alsaberi, Tsuyoshi Inoue, Tomoharu Oka
Abstract The youngest known Galactic supernova remnant (SNR) G1.9+0.3 has high-velocity supernova shock beyond 10000 km s−1, and it is considered to be one of the major candidates of a PeVatron. Despite these outstanding properties, the surrounding interstellar matter of this object is poorly understood. We investigated the interstellar gas toward G1.9+0.3 using the 12CO(J = 3−2) data with the angular resolution of 15″ obtained by the CHIMPS2 survey by the James Clerk Maxwell Telescope, and discovered three individual clouds at −1, 7, and 45 km s−1. From its morphological and velocity structures, the −1 km s−1 cloud, having the largest velocity width >20 km s−1 and located at the distance of the Galactic Center, is possibly associated with the SNR. The associated cloud shows a cavity structure both in space and velocity and coincides well with the SNR. We found that the associated cloud has higher column densities toward three bright, radio synchrotron-emitted rims where the radial expansion velocity of the supernova shock is decelerated, and the cloud is faint in the other parts of the SNR. This is the first direct evidence indicating that the highly anisotropic expansion of G1.9+0.3 observed by previous studies results from the deceleration by the interaction between the supernova shock and surrounding dense interstellar medium.
已知最年轻的银河系超新星遗迹(SNR) G1.9+0.3具有超过10000 km s−1的高速超新星激波，被认为是PeVatron的主要候选者之一。尽管有这些杰出的特性，但人们对这个天体周围的星际物质知之甚少。我们利用詹姆斯克拉克麦克斯韦望远镜(James Clerk Maxwell Telescope)对黑猩猩2巡天获得的角分辨率为15″的12CO(J = 3−2)数据研究了G1.9+0.3方向的星际气体，并在- 1、7和45 km s−1处发现了三个独立的云。从其形态和速度结构来看，- 1 km s - 1的云，其最大速度宽度为20 km s - 1，位于银河系中心的距离，可能与信噪比有关。伴生云在空间和速度上均呈空腔结构，与信噪比吻合较好。我们发现，在超新星激波的径向膨胀速度减慢的三个明亮的射电同步辐射边缘处，相关云团的柱密度较高，而在信噪比的其他部分，云团的柱密度较暗。这是第一个直接证据，表明先前研究中观测到的G1.9+0.3的高度各向异性膨胀是超新星激波与周围致密星际介质相互作用减速的结果。
{"title":"Discovery of a molecular cloud possibly associated with the youngest Galactic SNR G1.9+0.3","authors":"Rei Enokiya, Hidetoshi Sano, Miroslav D Filipović, Rami Z E Alsaberi, Tsuyoshi Inoue, Tomoharu Oka","doi":"10.1093/pasj/psad054","DOIUrl":"https://doi.org/10.1093/pasj/psad054","url":null,"abstract":"Abstract The youngest known Galactic supernova remnant (SNR) G1.9+0.3 has high-velocity supernova shock beyond 10000 km s−1, and it is considered to be one of the major candidates of a PeVatron. Despite these outstanding properties, the surrounding interstellar matter of this object is poorly understood. We investigated the interstellar gas toward G1.9+0.3 using the 12CO(J = 3−2) data with the angular resolution of 15″ obtained by the CHIMPS2 survey by the James Clerk Maxwell Telescope, and discovered three individual clouds at −1, 7, and 45 km s−1. From its morphological and velocity structures, the −1 km s−1 cloud, having the largest velocity width &gt;20 km s−1 and located at the distance of the Galactic Center, is possibly associated with the SNR. The associated cloud shows a cavity structure both in space and velocity and coincides well with the SNR. We found that the associated cloud has higher column densities toward three bright, radio synchrotron-emitted rims where the radial expansion velocity of the supernova shock is decelerated, and the cloud is faint in the other parts of the SNR. This is the first direct evidence indicating that the highly anisotropic expansion of G1.9+0.3 observed by previous studies results from the deceleration by the interaction between the supernova shock and surrounding dense interstellar medium.","PeriodicalId":20733,"journal":{"name":"Publications of the Astronomical Society of Japan","volume":"54 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135369645","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
We present early-stage analyses of low-resolution (R = 1000) optical spectra and near-infrared light curves of the bright Type II supernova (SN II) 2023ixf in the notable nearby face-on spiral galaxy M 101, which were obtained from t = 1.7 to 8.0 d. Our first spectrum showed remarkable emission features of the Balmer series, He ii, N iii, C iv, and N iv with a strong blue continuum. Compared with the SNe II which show flash-ionized features, we suggest that this SN could be categorized as a high-luminosity SN II with a nitrogen/helium-rich circumstellar material (CSM), e.g., SNe 2014G, 2017ahn, and 2020pni. The Hα emission line can be tentatively explained by a narrower component with a velocity of <300 km s−1 and a broader one with ∼2200 km s−1. The near-infrared light curves were well consistent with those of the another luminous SN 2017ahn, and its absolute magnitudes are located at the bright end of the luminosity distribution of SNe II. These observational facts support that SN 2023ixf is well consistent with high-luminosity SNe II showing evidence of a dense nitrogen/helium-rich CSM.
本文在t = 1.7 ~ 8.0 d期间，对m101附近的明亮II型超新星(SN II) 2023ixf的低分辨率(R = 1000)光谱和近红外光曲线进行了早期分析。我们的第一个光谱显示了Balmer系列，He ii, N iii, C iv和N iv的显著发射特征，具有强烈的蓝色连续体。与具有闪烁电离特征的SNe II相比，我们认为该SN可归类为具有富氮/氦的星周物质(CSM)的高亮度SN II，如SNe 2014G、2017ahn和2020pni。Hα发射谱线可以暂时用一个速度<300 km s - 1的较窄分量和一个速度为~ 2200 km s - 1的较宽分量来解释。其近红外光曲线与另一颗发光的SN 2017ahn的近红外光曲线一致，其绝对星等位于SNe II亮度分布的明亮端。这些观测结果支持了SN 2023ixf与高亮度SNe II的一致性，显示了致密的富含氮/氦的CSM的证据。
{"title":"Bright Type II supernova 2023ixf in M 101: A quick analysis of the early-stage spectra and near-infrared light curves","authors":"M. Yamanaka, M. Fujii, T. Nagayama","doi":"10.1093/pasj/psad051","DOIUrl":"https://doi.org/10.1093/pasj/psad051","url":null,"abstract":"\u0000 We present early-stage analyses of low-resolution (R = 1000) optical spectra and near-infrared light curves of the bright Type II supernova (SN II) 2023ixf in the notable nearby face-on spiral galaxy M 101, which were obtained from t = 1.7 to 8.0 d. Our first spectrum showed remarkable emission features of the Balmer series, He ii, N iii, C iv, and N iv with a strong blue continuum. Compared with the SNe II which show flash-ionized features, we suggest that this SN could be categorized as a high-luminosity SN II with a nitrogen/helium-rich circumstellar material (CSM), e.g., SNe 2014G, 2017ahn, and 2020pni. The Hα emission line can be tentatively explained by a narrower component with a velocity of <300 km s−1 and a broader one with ∼2200 km s−1. The near-infrared light curves were well consistent with those of the another luminous SN 2017ahn, and its absolute magnitudes are located at the bright end of the luminosity distribution of SNe II. These observational facts support that SN 2023ixf is well consistent with high-luminosity SNe II showing evidence of a dense nitrogen/helium-rich CSM.","PeriodicalId":20733,"journal":{"name":"Publications of the Astronomical Society of Japan","volume":"30 1","pages":""},"PeriodicalIF":2.3,"publicationDate":"2023-08-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84105880","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The upper-mass limit of a white dwarf star is predicted to be 1.44 ${M}_{odot} $ based on an ideally degenerate Fermi electron gas at a temperature of absolute zero. However, more conditions should be considered, such as temperature and charge. In this research, first, we use the grand partition function in statistical mechanics to build expressions for the electron gas pressure and the particle number depending on temperature. At 1.16 × 107 K, there is a total of about 1.50 × 10−4 electrons exceeding the Fermi energy, and about 1.50 × 10−7 at 1.16 × 104 K. Because some of these Fermi electrons are extremely relativistic, some of them can escape the gravity and some return to the star after leaving. These two mechanisms result in a positively charged star and the net positive charges produce a repulsive force and pressure against gravity. The increased pressure is comparable to that of the Fermi electron gas at T = 0 when the star is charged at 1020 C. The net charges will decrease the mass density of the star but increase the upper-mass limit.
{"title":"The additional pressure of white dwarf stars generated by net charges","authors":"Ting-Han Pei","doi":"10.1093/pasj/psad047","DOIUrl":"https://doi.org/10.1093/pasj/psad047","url":null,"abstract":"\u0000 The upper-mass limit of a white dwarf star is predicted to be 1.44 ${M}_{odot} $ based on an ideally degenerate Fermi electron gas at a temperature of absolute zero. However, more conditions should be considered, such as temperature and charge. In this research, first, we use the grand partition function in statistical mechanics to build expressions for the electron gas pressure and the particle number depending on temperature. At 1.16 × 107 K, there is a total of about 1.50 × 10−4 electrons exceeding the Fermi energy, and about 1.50 × 10−7 at 1.16 × 104 K. Because some of these Fermi electrons are extremely relativistic, some of them can escape the gravity and some return to the star after leaving. These two mechanisms result in a positively charged star and the net positive charges produce a repulsive force and pressure against gravity. The increased pressure is comparable to that of the Fermi electron gas at T = 0 when the star is charged at 1020 C. The net charges will decrease the mass density of the star but increase the upper-mass limit.","PeriodicalId":20733,"journal":{"name":"Publications of the Astronomical Society of Japan","volume":"1 1","pages":""},"PeriodicalIF":2.3,"publicationDate":"2023-08-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82292092","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Solar prominences are cool and dense plasma supported by the magnetic field in the solar corona. They are composed of fine-scale structures called threads. Prominences are heated by the incident radiation from the solar atmosphere, but previous studies have shown that additional heating is necessary to maintain the temperature of prominences of about 104 K. This study aims to investigate quantitatively the mechanical heating of the prominences from observations. We performed spectroscopic observations of prominences in Hα (6563 Å), Hβ (4861 Å), and Ca ii IR (8542 Å) with the Domeless Solar Telescope at Hida observatory. The plasma parameters of the prominences are estimated by fittings of line profiles using the single-slab model and by solving the statistical equilibrium equation. By assuming that the turbulent motion is the manifestation of propagating Alfvén waves, net radiative losses and Alfvén wave energy flux in the prominences are estimated from these parameters. As a result, it was found that the energy flux by Alfvén waves is sufficient to compensate for the net radiative losses in most regions of the central part of the prominences. On the other hand, Alfvén wave energy flux tends to be insufficient at the outer part of prominences. In such regions, another heating mechanism such as enthalpy flux of mixing with coronal plasma needs to be considered.
太阳日珥是由日冕磁场支持的冷而致密的等离子体。它们是由称为线程的精细结构组成的。日珥被来自太阳大气的入射辐射加热，但先前的研究表明，额外的加热是必要的，以保持日珥的温度约104 K。本研究旨在从观测中定量地探讨日珥的机械加热。我们利用Hida天文台的无丘太阳望远镜对Hα (6563 Å)、Hβ (4861 Å)和Ca ii IR (8542 Å)的日珥进行了光谱观测。利用单平板模型拟合直线轮廓，通过求解统计平衡方程，估计了日珥的等离子体参数。假设湍流运动是传播的alfvsamn波的表现，从这些参数估计日珥的净辐射损失和alfvsamn波能量通量。结果发现，在日珥中心大部分地区，alfvsamn波的能量通量足以补偿净辐射损失。另一方面，在日珥的外围，alfvsamn波能量通量往往不足。在这些区域，需要考虑其他加热机制，如与日冕等离子体混合的焓通量。
{"title":"Plasma diagnostics and Alfvén wave heating of solar prominences by multiwavelength observations","authors":"Yuki Hashimoto, K. Ichimoto, Yuwei Huang","doi":"10.1093/pasj/psad049","DOIUrl":"https://doi.org/10.1093/pasj/psad049","url":null,"abstract":"\u0000 Solar prominences are cool and dense plasma supported by the magnetic field in the solar corona. They are composed of fine-scale structures called threads. Prominences are heated by the incident radiation from the solar atmosphere, but previous studies have shown that additional heating is necessary to maintain the temperature of prominences of about 104 K. This study aims to investigate quantitatively the mechanical heating of the prominences from observations. We performed spectroscopic observations of prominences in Hα (6563 Å), Hβ (4861 Å), and Ca ii IR (8542 Å) with the Domeless Solar Telescope at Hida observatory. The plasma parameters of the prominences are estimated by fittings of line profiles using the single-slab model and by solving the statistical equilibrium equation. By assuming that the turbulent motion is the manifestation of propagating Alfvén waves, net radiative losses and Alfvén wave energy flux in the prominences are estimated from these parameters. As a result, it was found that the energy flux by Alfvén waves is sufficient to compensate for the net radiative losses in most regions of the central part of the prominences. On the other hand, Alfvén wave energy flux tends to be insufficient at the outer part of prominences. In such regions, another heating mechanism such as enthalpy flux of mixing with coronal plasma needs to be considered.","PeriodicalId":20733,"journal":{"name":"Publications of the Astronomical Society of Japan","volume":"11 1","pages":""},"PeriodicalIF":2.3,"publicationDate":"2023-07-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74053385","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Retraction of: Transient jet ejections associated with limit-cycle behaviors in the very high state of black hole binaries","authors":"","doi":"10.1093/pasj/psad045","DOIUrl":"https://doi.org/10.1093/pasj/psad045","url":null,"abstract":"","PeriodicalId":20733,"journal":{"name":"Publications of the Astronomical Society of Japan","volume":"15 1","pages":""},"PeriodicalIF":2.3,"publicationDate":"2023-07-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87858517","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Asahi Fujishige, S. Yamauchi, K. Nobukawa, M. Nobukawa
The results of a Suzaku observation of the supernova remnant (SNR) G352.7−0.1 are presented in this paper. We conducted spectral analysis based on careful sky background estimation and found an emission line from Al at 1.6 keV, in addition to previously detected emission lines from Mg, Si, S, Ar, Ca, and Fe ions. The X-ray spectrum in the 0.7–10 keV band is represented by a two-component ionizing plasma model with different temperatures and ionization timescales. Based on the results, properties of the X-ray emitting plasma and the explosion type are discussed.
{"title":"Suzaku spectral analysis of an X-ray emitting plasma in the supernova remnant G352.7−0.1","authors":"Asahi Fujishige, S. Yamauchi, K. Nobukawa, M. Nobukawa","doi":"10.1093/pasj/psad048","DOIUrl":"https://doi.org/10.1093/pasj/psad048","url":null,"abstract":"\u0000 The results of a Suzaku observation of the supernova remnant (SNR) G352.7−0.1 are presented in this paper. We conducted spectral analysis based on careful sky background estimation and found an emission line from Al at 1.6 keV, in addition to previously detected emission lines from Mg, Si, S, Ar, Ca, and Fe ions. The X-ray spectrum in the 0.7–10 keV band is represented by a two-component ionizing plasma model with different temperatures and ionization timescales. Based on the results, properties of the X-ray emitting plasma and the explosion type are discussed.","PeriodicalId":20733,"journal":{"name":"Publications of the Astronomical Society of Japan","volume":"4 1","pages":""},"PeriodicalIF":2.3,"publicationDate":"2023-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87377766","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Kuilu Yang, Yong Zhang, J. Qiu, Yina Ao, Xiaohu Li
We present an unbiased molecular line survey toward the carbon-rich circumstellar envelope CIT 6 carried out between 90 and 116 GHz with the Arizona Radio Observatory 12 m telescope. A total of 42 lines assigned to 10 molecular species and four isotopologues are detected. Despite the absence of any newly identified circumstellar molecules, several transitions are freshly reported for this object. This work is a complement to our previous line survey toward CIT 6 in the frequency ranges of 36–49 GHz and 131–268 GHz. Based on the measurements and in combination with previously published data, we perform a rotation-diagram analysis to determine the column densities, excitation temperatures, and fractional abundances of the molecules. The excitation temperature varies along the radius. The abundance pattern of CIT 6 is broadly consistent with that of the prototype C-star IRC +10216 at the specified detection sensitivity, indicating that the molecular richness in IRC +10216 cannot be attributed to an interpretation of unusual chemistry. Nevertheless, subtle distinctions between the two C-stars are found. The higher abundance of carbon-chain molecules and lower 12C$/$13C ratio in CIT 6 compared to IRC +10216 imply that the former is more massive or in a more evolved phase than the latter.
{"title":"A 3 mm molecular line survey toward the C-star envelope CIT 6","authors":"Kuilu Yang, Yong Zhang, J. Qiu, Yina Ao, Xiaohu Li","doi":"10.1093/pasj/psad043","DOIUrl":"https://doi.org/10.1093/pasj/psad043","url":null,"abstract":"\u0000 We present an unbiased molecular line survey toward the carbon-rich circumstellar envelope CIT 6 carried out between 90 and 116 GHz with the Arizona Radio Observatory 12 m telescope. A total of 42 lines assigned to 10 molecular species and four isotopologues are detected. Despite the absence of any newly identified circumstellar molecules, several transitions are freshly reported for this object. This work is a complement to our previous line survey toward CIT 6 in the frequency ranges of 36–49 GHz and 131–268 GHz. Based on the measurements and in combination with previously published data, we perform a rotation-diagram analysis to determine the column densities, excitation temperatures, and fractional abundances of the molecules. The excitation temperature varies along the radius. The abundance pattern of CIT 6 is broadly consistent with that of the prototype C-star IRC +10216 at the specified detection sensitivity, indicating that the molecular richness in IRC +10216 cannot be attributed to an interpretation of unusual chemistry. Nevertheless, subtle distinctions between the two C-stars are found. The higher abundance of carbon-chain molecules and lower 12C$/$13C ratio in CIT 6 compared to IRC +10216 imply that the former is more massive or in a more evolved phase than the latter.","PeriodicalId":20733,"journal":{"name":"Publications of the Astronomical Society of Japan","volume":"58 1","pages":""},"PeriodicalIF":2.3,"publicationDate":"2023-07-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90903460","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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