Article
Astronomy & Astrophysics
Vineet Rawat, M. R. Samal, D. L. Walker, A. Zavagno, A. Tej, G. Marton, D. K. Ojha, Davide Elia, W. P. Chen, J. Jose, C. Eswaraiah
Summary: Studying the properties of clouds in the early stages of their evolution provides an opportunity to test cluster formation processes. By analyzing the CO, Herschel, and UKIDSS observations of cloud G148.24+00.41, we find that it is a high mass, low dust temperature cloud with a nearly circular shape. Comparing its properties with nearby molecular clouds, we determine that it is similar to the Orion-A molecular cloud in terms of mass, size, and dense gas fraction. Our analysis also suggests that the cloud has the potential to form a cluster in the mass range of 2000-3000 M-circle dot through hierarchical collapse and assembly of gas and stars.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2023)
Article
Astronomy & Astrophysics
D. A. Ladeyschikov, M. S. Kirsanova, A. M. Sobolev, M. Thomasson, V Ossenkopf-Okada, M. Juvela, S. A. Khaibrakhmanov, E. A. Popova
Summary: This study investigates the relationship between the distributions of young stellar objects (YSOs) of different ages and the gas-dust constituents of the S254-S258 star formation complex, revealing a tighter correlation of the gas-dust tracers with class I YSO distribution compared to class II YSOs. It suggests that class I YSOs born in the central cluster S255-IR have enough time to travel through the entire star formation region as they evolve into class II YSOs. Despite the complex formation of YSO clusters in the non-uniform medium, class II YSO clusters in the region may contain objects born in various locations within the complex.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2021)
Article
Astronomy & Astrophysics
A. Avison, G. A. Fuller, N. Asabre Frimpong, S. Etoka, M. Hoare, B. M. Jones, N. Peretto, A. Traficante, F. van der Tak, J. E. Pineda, M. Beltran, F. Wyrowski, M. Thompson, S. Lumsden, Z. Nagy, T. Hill, S. Viti, F. Fontani, P. Schilke
Summary: The role of massive stars in shaping the interstellar medium in their host galaxy is significant. This study presents a sample of massive star-forming regions observed with ALMA and explores their fragmentation, clustering, and flux density properties. The sample contains multiple fragments per field, and the fragmentation scales are often larger than the thermal Jeans length. Furthermore, a tentative evolutionary trend is observed between the clump luminosity and the spectral line richness of the fields.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2023)
Article
Astronomy & Astrophysics
M. Juvela, E. Mannfors
Summary: The properties of filamentary structures in star-forming interstellar clouds were compared using mid-infrared absorption and far-infrared dust emission in the Orion Molecular Cloud 3 (OMC-3). The results show that the widths of the OMC-3 filaments were consistent between the mid-infrared and far-infrared analyses. However, there were potential sources of systematic error, particularly at high column densities and in weak radiation fields.
ASTRONOMY & ASTROPHYSICS
(2023)
Article
Astronomy & Astrophysics
Yuping Tang, Q. Daniel Wang, Grant W. Wilson
Summary: Through a Bayesian modeling and joint spectral energy distribution analysis, this study investigates the dust properties in the Central Molecular Zone of our Galaxy, revealing an increasing trend of dust spectral index beta towards dense peaks. This environmental dependence of beta could have significant implications for the determination of dust temperature in other studies.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2021)
Article
Astronomy & Astrophysics
A. D. P. Howard, A. P. Whitworth, M. J. Griffin, K. A. Marsh, M. W. L. Smith
Summary: The PPMAP algorithm reanalyzed observations of the L1688 and L1689 subregions of the Ophiuchus molecular cloud, delivering high-resolution maps and more accurate dust optical depths. Most filaments and pre-stellar cores are located in regions with high N-H2 values, with some exceptions influenced by feedback from nearby stars. The study suggests that most starless cores are likely to disperse instead of evolving into pre-stellar cores.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2021)
Article
Astronomy & Astrophysics
R. L. Pitts, L. E. Kristensen, J. K. Jorgensen, S. J. van der Walt
Summary: This study derived the masses, luminosities, and envelope density profiles for eight sources in Cygnus-X and compared them with similar sources in the literature. The results show that the trends in envelope parameters for high-mass protostars are statistically indistinguishable from trends in the same variables for low-mass protostars.
ASTRONOMY & ASTROPHYSICS
(2022)
Article
Astronomy & Astrophysics
E. Mannfors, M. Juvela, L. Bronfman, D. J. Eden, J. He, G. Kim, K-T Kim, H. Kirppu, T. Liu, J. Montillaud, H. Parsons, P. Sanhueza, H. Shang, A. Soam, K. Tatematsu, A. Traficante, M. S. Vaisala, C. W. Lee
Summary: The study aimed to characterize a diverse selection of dense, potentially star-forming cores, clumps, and clouds within the Milky Way in terms of their dust emission and SF activity by analyzing 53 fields observed in the JCMT SCUBA-2 continuum survey SCOPE and mapped with Herschel. The study found 529 dense clumps with high column densities, low temperatures, and estimated submillimeter beta values. Furthermore, the masses, sizes, and temperatures of the sources were found to be correlated with distance, and the gravitational stability of the clumps was dependent on distance as well.
ASTRONOMY & ASTROPHYSICS
(2021)
Article
Astronomy & Astrophysics
Davide Elia, M. Merello, S. Molinari, E. Schisano, A. Zavagno, D. Russeil, P. Mege, P. G. Martin, L. Olmi, M. Pestalozzi, R. Plume, S. E. Ragan, M. Benedettini, D. J. Eden, T. J. T. Moore, A. Noriega-Crespo, R. Paladini, P. Palmeirim, S. Pezzuto, G. L. Pilbratt, K. L. J. Rygl, P. Schilke, F. Strafella, J. C. Tan, A. Traficante, A. Baldeschi, J. Bally, A. M. di Giorgio, E. Fiorellino, S. J. Liu, L. Piazzo, D. Polychroni
Summary: This study presents a 360-degree catalogue of physical properties of Hi-GAL compact sources detected between 70 and 500 µm. The analysis includes source luminosity, mass, temperature, and other bolometric quantities derived from spectral energy distribution data. The study also examines the statistical properties of these quantities with respect to source Galactic location and evolutionary stage, highlighting differences in masses and densities in the inner Galaxy which show a higher number of clumps potentially hosting massive star formation. There is no clear evidence of correlation between distance-independent parameters tracing source evolutionary status and spiral arm positions.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2021)
Article
Astronomy & Astrophysics
D. Rumble, J. Hatchell, H. Kirk, K. Pattle
Summary: Radiative feedback from OB stars in star-forming regions influences subsequent star formation by heating dust in the surrounding areas. The study quantifies the impact of different spectral type stars, with O-type stars showing the greatest temperature rises and heating extent, while B-type stars have a weaker heating effect. Even in local, 'low-mass' star-forming regions, 24% of the clumps are heated to at least 3 K above the base temperature expected from interstellar radiation heating, with a mean dust temperature of 24 K for heated clumps.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2021)
Article
Astronomy & Astrophysics
S. Pezzuto, M. Benedettini, J. Di Francesco, P. Palmeirim, S. Sadavoy, E. Schisano, G. Li Causi, Ph. Andre, D. Arzoumanian, J. -Ph. Bernard, S. Bontemps, D. Elia, E. Fiorellino, J. M. Kirk, V. Konyves, B. Ladjelate, A. Men'shchikov, F. Motte, L. Piccotti, N. Schneider, L. Spinoglio, D. Ward-Thompson, C. D. Wilson
Summary: In this study, the complex of star-forming regions in Perseus was analyzed using images taken with the Herschel ESA satellite. Various analysis techniques were employed to identify and characterize compact cores in the regions, as well as to model distance variations and gradients across the Perseus cloud. The study also explored the relationship between filamentary structures in Perseus and star formation, deriving insights into the stability and formation efficiency of prestellar cores.
ASTRONOMY & ASTROPHYSICS
(2021)
Article
Astronomy & Astrophysics
Jian-Wen Zhou, Shanghuo Li, Hong-Li Liu, Yaping Peng, Siju Zhang, Feng-Wei Xu, Chao Zhang, Tie Liu, Jin-Zeng Li
Summary: This study investigates the formation of hub-filament structures in the W33 complex by analyzing the velocity structures and their correlations with column density. It is suggested that the hub-filament structures are triggered by cloud-cloud collisions, and the non-thermal motions in W33-blue may originate from gravitationally driven collapse. However, the large-scale velocity gradient in W33-blue is likely influenced by cloud-cloud collisions and feedback from active star formation, rather than filament-rooted longitudinal inflow.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2023)
Article
Astronomy & Astrophysics
Kate Pattle, Shih-Ping Lai, Melvyn Wright, Simon Coude, Richard Plambeck, Thiem Hoang, Ya-Wen Tang, Pierre Bastien, Chakali Eswaraiah, Ray S. Furuya, Jihye Hwang, Shu-ichiro Inutsuka, Kee-Tae Kim, Florian Kirchschlager, Woojin Kwon, Chang Won Lee, Sheng-Yuan Liu, Aran Lyo, Nagayoshi Ohashi, Mark G. Rawlings, Mehrnoosh Tahani, Motohide Tamura, Archana Soam, Jia-Wei Wang, Derek Ward-Thompson
Summary: ALMA Band 7 polarization observations of the OMC-1 region of the Orion molecular clouds showed that the polarization pattern was influenced by the radiation field of the high-mass protostar Orion Source I. The optically thick disc of the protostar likely caused polarization from dust self-scattering, revealing a concentric geometry around Source I. The extreme luminosity of Source I may cause grains to precess around the radiation anisotropy vector, supporting the emission from the Source I outflow cavity wall.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2021)
Article
Astronomy & Astrophysics
E. Fiorellino, D. Elia, Ph Andre, A. Men'shchikov, S. Pezzuto, E. Schisano, V Konyves, D. Arzoumanian, M. Benedettini, D. Ward-Thompson, A. Bracco, J. Di Francesco, S. Bontemps, J. Kirk, F. Motte, S. Molinari
Summary: The Herschel Gould Belt survey investigated the distribution and characteristics of dense cores in the Serpens star-forming region, revealing the influence of the prestellar phase on the star formation process. The majority of prestellar cores were found to form on filamentary structures, supporting the hypothesis that prestellar cores mostly form on filaments.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2021)
Article
Astronomy & Astrophysics
R. Siebenmorgen, J. Smoker, J. Krelowski, Karl Gordon, Rolf Chini
Summary: By merging a sample of 820 reddening curves of stars, the highest-quality Milky Way reddening curve sample has been obtained, confirming previous estimates. A future paper in this series will use the current sample of precise reddening curves and combine them with polarization data to study the properties of dark dust.
ASTRONOMY & ASTROPHYSICS
(2023)
Article
Astronomy & Astrophysics
Hsi-Wei Yen, Patrick M. Koch, Chin-Fei Lee, Naomi Hirano, Nagayoshi Ohashi, Jinshi Sai (Insa Choi), Shigehisa Takakuwa, Ya-Wen Tang, Ken'ichi Tatematsu, Bo Zhao
Summary: To study the transportation of magnetic flux in protostellar sources, we analyzed multiple datasets for the Class 0 protostar HH 211. Our analysis suggests an increase in magnetic field strength and mass-to-flux ratio from larger to smaller scales. We propose that this increase in mass-to-flux ratio indicates partial decoupling of the magnetic field from neutral matter and efficient ambipolar diffusion in the protostellar envelope, supporting the formation of a Keplerian disk in HH 211.
ASTROPHYSICAL JOURNAL
(2023)
Article
Astronomy & Astrophysics
Siju Zhang, Ke Wang, Tie Liu, Annie Zavagno, Mika Juvela, Hongli Liu, Anandmayee Tej, Amelia M. Stutz, Shanghuo Li, Leonardo Bronfman, Qizhou Zhang, Paul F. Goldsmith, Chang Won Lee, Enrique Vazquez-Semadeni, Ken'ichi Tatematsu, Wenyu Jiao, Fengwei Xu, Chao Wang, Jian-Wen Zhou
Summary: This study uses ALMA observations to investigate the formation of massive stars triggered by ionization feedback. The results suggest that radiation-driven implosion is responsible for the formation of embedded cores and protostars within the ionizing feedback-driven structure. Additionally, filamentary gas structures fuel mass towards the cores in the bright-rimmed cloud. These findings reveal the operation of the combined process of radiation-driven implosion and clump-fed process in this massive bright-rimmed cloud.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2023)
Article
Astronomy & Astrophysics
Stella Koch Ocker, James M. Cordes, Shami Chatterjee, Di Li, Chen-Hui Niu, James W. McKee, Casey J. Law, Reshma Anna-Thomas
Summary: Fast radio bursts (FRBs) are millisecond-time-scale radio transients originated from highly magnetized compact objects primarily detected in extragalactic sources and undergo scattering due to plasma density fluctuations. We report the observation of variable scattering times in the repeating FRB 20190520B, which can deviate from the typical power law. These scattering variations are likely caused by inhomogeneous plasma in the circumsource medium and can provide insights into small-scale processes within FRB environments.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2023)
Article
Astronomy & Astrophysics
Derek Ward-Thompson, Janik Karoly, Kate Pattle, Anthony Whitworth., Jason Kirk., David. Berry, Pierre Bastien, Tao-Chung Ching, Simon Coude, Jihye Hwang, Woojin Kwon, Archana Soam, Jia-Wei Wang, Tetsuo Hasegawa, Shih-Ping Lai, Keping Qiu, Doris Arzoumanian, Tyler L. Bourke, Do-Young Byun, Huei-Ru Vivien Chen, Wen Ping Chen, Mike Chen, Zhiwei Chen, Jungyeon Cho, Minho Choi, Youngwoo Choi, Yunhee Choi, Antonio Chrysostomou, Eun Jung Chung, Sophia Dai, Victor Debattista, James Di Francesco, Pham Ngoc Diep, Yasuo Doi, Hao-Yuan Duan, Yan Duan, Chakali Eswaraiah, Lapo Fanciullo, Jason Fiege, Laura M. Fissel, Erica Franzmann, Per Friberg, Rachel Friesen, Gary Fuller, Ray Furuya, Tim Gledhill, Sarah Graves, Jane Greaves, Matt Griffin, Qilao Gu, Ilseung Han, Saeko Hayashi, Thiem Hoang, Martin Houde, Charles L. H. Hull, Tsuyoshi Inoue, Shu-ichiro Inutsuka, Kazunari Iwasaki, Il-Gyo Jeong, Doug Johnstone, Vera Koenyves, Ji-hyun Kang, Miju Kang, Akimasa Kataoka, Koji Kawabata, Francisca Kemper, Jongsoo Kim, Shinyoung Kim, Gwanjeong Kim, Kyoung Hee Kim, Mi-Ryang Kim, Kee-Tae Kim, Hyosung Kim, Florian Kirchschlager, Masato I. N. Kobayashi, Patrick M. Koch, Takayoshi Kusune, Jungmi Kwon, Kevin Lacaille, Chi-Yan Law, Chang Won Lee, Hyeseung Lee, Yong-Hee Lee, Chin-Fei Lee, Jeong-Eun Lee, Sang-Sung Lee, Di Li, Di Li, Guangxing Li, Hua-bai Li, Sheng-Jun Lin, Hong-Li Liu, Tie Liu, Sheng-Yuan Liu, Junhao Liu, Steven Longmore, Xing Lu, A-Ran Lyo, Steve Mairs, Masafumi Matsumura, Brenda Matthews, Gerald Moriarty-Schieven, Tetsuya Nagata, Fumitaka Nakamura, Hiroyuki Nakanishi, Nguyen Bich Ngoc, Nagayoshi Ohashi, Takashi Onaka, Geumsook Park, Harriet Parsons, Nicolas Peretto, Felix Priestley, Tae-Soo Pyo, Lei Qian, Ramprasad Rao, Jonathan Rawlings, Mark Rawlings, Brendan Retter, John Richer, Andrew Rigby, Sarah Sadavoy, Hiro Saito, Giorgio Savini, Masumichi Seta, Yoshito Shimajiri, Hiroko Shinnaga, Mehrnoosh Tahani, Motohide Tamura, Ya-Wen Tang, Xindi Tang, Kohji Tomisaka, Le Ngoc Tram, Yusuke Tsukamoto, Serena Viti, Hongchi Wang, Jintai Wu, Jinjin Xie, Meng-Zhe Yang, Hsi-Wei Yen, Hyunju Yoo, Jinghua Yuan, Hyeong-Sik Yun, Tetsuya Zenko, Guoyin Zhang, Yapeng Zhang, Chuan-Peng Zhang, Jianjun Zhou, Lei Zhu, Ilse de Looze, Philippe Andre, C. Darren Dowell, David Eden, Stewart Eyres, Sam Falle, Valentin J. M. Le Gouellec, Frederick Poidevin, Jean-Francois Robitaille, Sven van Loo
Summary: We conducted BISTRO Survey observations of the L1495A-B10 region in the Taurus molecular cloud and found a triangular network of dense filaments. Within these filaments, we identified nine starless cores in polarization, and observed that the core-scale magnetic field orientation is nearly perpendicular to the filaments. Furthermore, we discovered a transitional stage in early prestellar evolution and observed the sheet-like structure and its fragmentation into filaments, providing valuable insights into the transition from field-dominated to matter-dominated evolution.
ASTROPHYSICAL JOURNAL
(2023)
Article
Astronomy & Astrophysics
Yan Duan, Di Li, Paul F. Goldsmith, Laurent Pagani, Tao-Chung Ching, Shu Liu, Jinjin Xie, Chen Wang
Summary: Star formation can create bubbles and outflows that inject momentum and energy into the interstellar medium, affecting the overall energy balance of the molecular cloud. The study reports the identification of a new molecular bubble with an outflow, along with a Herbig-Haro object. Through the analysis of multiwavelength data, the spatial structure, energy injection, and dynamical timescale of the bubble have been investigated. This discovery provides additional observational evidence for the theory of stellar wind from T Tauri stars and enhances our understanding of stellar feedback in molecular clouds.
ASTROPHYSICAL JOURNAL
(2023)
Article
Astronomy & Astrophysics
Gan Luo, Zhi-Yu Zhang, Thomas G. Bisbas, Di Li, Ping Zhou, Ningyu Tang, Junzhi Wang, Pei Zuo, Nannan Yue
Summary: The cosmic-ray ionization rate (CRIR) is crucial for the formation and destruction of molecules in molecular clouds. This study proposes an alternative method to estimate the CRIR in diffuse clouds by analyzing the abundance ratios of OH/CO and HCO+/CO. It is found that the abundances of CO, OH, and HCO+ are proportional to zeta(2). The derived CRIR in the diffuse gas sample is higher than the average value measured at higher extinction, suggesting CR attenuation.
ASTROPHYSICAL JOURNAL
(2023)
Article
Astronomy & Astrophysics
Mao Yuan, Weiwei Zhu, Michael Kramer, Bo Peng, Jiguang Lu, Renxin Xu, Lijing Shao, Hong-Guang Wang, Lingqi Meng, Jiarui Niu, Rushuang Zhao, Chenchen Miao, Xueli Miao, Mengyao Xue, Yi Feng, Pei Wang, Di Li, Chengming Zhang, David J. Champion, Emmanuel Fonseca, Huanchen Hu, Jumei Yao, Paulo C. C. Freire, Yanjun Guo
Summary: We have identified three new weak pulse components in two known pulsars, PSR J0304+1932 and PSR J1518+4904. These components are emitted at a midpoint between the main emission beam and the interpulse beam, and exhibit a certain degree of separation from the main pulse peak. Our analysis also reveals correlations between these weak pulses and their main pulses, suggesting that they originate from the same pole. Additionally, our estimation of the emission altitude suggests that these pulse components are high-altitude emissions, challenging current pulsar emission models.
ASTROPHYSICAL JOURNAL
(2023)
Article
Astronomy & Astrophysics
Mehrnoosh Tahani, Pierre Bastien, Ray S. Furuya, Kate Pattle, Doug Johnstone, Doris Arzoumanian, Yasuo Doi, Tetsuo Hasegawa, Shu-ichiro Inutsuka, Simon Coude, Laura Fissel, Michael Chun-Yuan Chen, Frederick Poidevin, Sarah Sadavoy, Rachel Friesen, Patrick M. Koch, James Di Francesco, Gerald H. Moriarty-Schieven, Zhiwei Chen, Eun Jung Chung, Chakali Eswaraiah, Lapo Fanciullo, Tim Gledhill, Valentin J. M. Le Gouellec, Thiem Hoang, Jihye Hwang, Ji-hyun Kang, Kyoung Hee Kim, Florian Kirchschlager, Woojin Kwon, Chang Won Lee, Hong-Li Liu, Takashi Onaka, Mark G. Rawlings, Archana Soam, Motohide Tamura, Xindi Tang, Kohji Tomisaka, Anthony P. Whitworth, Jungmi Kwon, Thuong D. Hoang, Matt Redman, David Berry, Tao-Chung Ching, Jia-Wei Wang, Shih-Ping Lai, Keping Qiu, Derek Ward-Thompson, Martin Houde, Do-Young Byun, Huei-Ru Vivien Chen, Wen Ping Chen, Jungyeon Cho, Minho Choi, Yunhee Choi, Antonio Chrysostomou, Pham Ngoc Diep, Hao-Yuan Duan, Jason Fiege, Erica Franzmann, Per Friberg, Gary Fuller, Sarah F. Graves, Jane S. Greaves, Matt J. Griffin, Qilao Gu, Ilseung Han, Jennifer Hatchell, Saeko S. Hayashi, Charles L. H. Hull, Tsuyoshi Inoue, Kazunari Iwasaki, Il-Gyo Jeong, Yoshihiro Kanamori, Miju Kang, Sung-ju Kang, Akimasa Kataoka, Koji S. Kawabata, Francisca Kemper, Gwanjeong Kim, Jongsoo Kim, Kee-Tae Kim, Mi-Ryang Kim, Shinyoung Kim, Jason M. Kirk, Masato I. N. Kobayashi, Vera Konyves, Takayoshi Kusune, Kevin Lacaille, Chi-Yan Law, Chin-Fei Lee, Hyeseung Lee, Jeong-Eun Lee, Sang-Sung Lee, Yong-Hee Lee, Dalei Li, Di Li, Hua-bai Li, Junhao Liu, Sheng-Yuan Liu, Tie Liu, Ilse de Looze, A-Ran Lyo, Steve Mairs, Masafumi Matsumura, Brenda C. Matthews, Tetsuya Nagata, Fumitaka Nakamura, Hiroyuki Nakanishi, Nagayoshi Ohashi, Geumsook Park, Harriet Parsons, Nicolas Peretto, Tae-Soo Pyo, Lei Qian, Ramprasad Rao, Brendan Retter, John Richer, Andrew Rigby, Hiro Saito, Giorgio Savini, Anna M. M. Scaife, Masumichi Seta, Yoshito Shimajiri, Hiroko Shinnaga, Ya-Wen Tang, Yusuke Tsukamoto, Serena Viti, Hongchi Wang, Hsi-Wei Yen, Hyunju Yoo, Jinghua Yuan, Hyeong-Sik Yun, Tetsuya Zenko, Chuan-Peng Zhang, Guoyin Zhang, Yapeng Zhang, Jianjun Zhou, Lei Zhu, Philippe Andre, C. Darren Dowell, Stewart P. S. Eyres, Sam Falle, Sven van Loo, Jean-Francois Robitaille
Summary: We study the polarization patterns and magnetic field morphologies associated with Hii regions in the NGC 6334 molecular cloud. We find that in some bubbles, the gas and magnetic field lines have been pushed away from the bubble, resulting in an almost tangential magnetic field morphology. However, in the densest part of NGC 6334, where the magnetic field morphology is similar to an hourglass, the polarization observations do not show any impact from Hii regions. We also identify nested radial polarization patterns in a bubble to the south of NGC 6334, corresponding to the previously observed bipolar structure.
ASTROPHYSICAL JOURNAL
(2023)
Article
Astronomy & Astrophysics
Chong Li, Keping Qiu, Di Li, Hongchi Wang, Yue Cao, Junhao Liu, Yuehui Ma, Chenglin Yang
Summary: Using data from the Five-hundred-meter Aperture Spherical radio Telescope, we examined the cold atomic gas in the Cygnus X North region. The most prominent feature was a filamentary H i cloud associated with the principal molecular filament. Our study focused on the transition process from atomic filament to molecular filament. We found that the presence of H ii regions Cygnus OB2 and G081.920+00.138 played a crucial role in shaping the atomic filament and promoting the formation of the molecular filament.
ASTROPHYSICAL JOURNAL LETTERS
(2023)
Article
Astronomy & Astrophysics
P. Padoan, V-M Pelkonen, M. Juvela, T. Haugbolle, A. Nordlund
Summary: Characterizing pre-stellar cores in star-forming regions is crucial for testing theoretical models of star formation. However, extracting real cores from dust-continuum observations is challenging due to projection effects. This study examines core extraction in both idealized column-density maps and synthetic ALMA observations. It finds that derived core masses are unreliable, with a weak correlation between synthetic ALMA and three-dimensional cores. Proper guidance from realistic simulations is essential for using ALMA observations at kpc distances to test star formation models.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2023)
Article
Astronomy & Astrophysics
Zong-Hao Chen, Shan-Ping You, Xu-Hong Yu, Pei Wang, Di Li, Xiao-Yao Xie, Zhi-Jie Liu, Chun-Qing Wang, Peng Zeng, Bin Zhang
Summary: RFI interference is a well-recognized issue in radio astronomy research, and we propose an intuitive and powerful RFI mitigation pipeline (CCF-ST) to improve the quality of data in pulsar and fast radio burst searches. The CCF-ST is a spatial filter constructed using the cross-correlation function (CCF) and Sum-Threshold (ST) algorithm. The performance of CCF-ST is evaluated using data from CRAFTS, and it outperforms other methods such as PRESTO's rfifind and ArPLS-ST in terms of reducing data loss rate and improving signal-to-noise ratio.
RESEARCH IN ASTRONOMY AND ASTROPHYSICS
(2023)
Article
Agronomy
Ziying Wang, Di Li, Nazim S. Gruda, Chunwu Zhu, Zengqiang Duan, Xun Li
Summary: Producing selenium-enriched vegetables through hydroponics is a convenient and effective way to provide nutrient-rich food. However, increased CO2 fertilization can negatively affect mineral concentrations in the edible parts. Through the study, it was found that a Se supply level of 0.125 mg Se L-1 can protect photosynthetic pigments and stimulate stomatal opening, leading to higher net photosynthesis rate and transpiration rate.
Article
Astronomy & Astrophysics
Yuhao Zhu, Chenhui Niu, Xianghan Cui, Di Li, Yi Feng, Chaowei Tsai, Pei Wang, Yongkun Zhang, Fanyi Meng, Zheng Zheng
Summary: This study aims to determine whether multi-structural one-off FRBs and repeaters share similarities by analyzing the relationship between the FRB event rate and the star formation rate, and using statistical testing methods. Energy functions for four subsamples were calculated based on the CHIME/FRB Catalog 1, and it was found that all subsamples show a similar cosmological evolution trend. However, the multi-structural one-offs and repeaters were found to be distinguishable from the KS and MWW tests.
Article
Astronomy & Astrophysics
Qiu-yi Luo, Tie Liu, Aaron T. Lee, Stella S. R. Offner, James di Francesco, Doug Johnstone, Mika Juvela, Paul F. Goldsmith, Sheng-Li Qin, Xiaofeng Mai, Xun-chuan Liu, Patricio Sanhueza, Feng-Wei Xu, Ken'ichi Tatematsu, Somnath Dutta, Huei-Ru Vivien Chen, Shanghuo Li, Aiyuan Yang, Sheng-Yuan Liu, Chin-Fei Lee, Naomi Hirano, Chang Won Lee, Dipen Sahu, Hsien Shang, Shih-Ying Hsu, Leonardo Bronfman, Woojin Kwon, M. G. Rawlings, David Eden, Xing Lu, Qi-lao Gu, Zhiyuan Ren, D. Ward-Thompson, Zhi-Qiang Shen
Summary: The formation process of multiple-star systems in low-mass star formation is poorly understood. This study uses ALMA observations to investigate a forming quadruple protostellar system, G206.93-16.61E2, in the Orion B molecular cloud. The results reveal four compact objects, with two being young stellar objects and the other two likely in prestellar phase. Ribbon-like structures connecting the objects are found, which are suggested to trace accretion flows and serve as gas bridges connecting the protostars. A complex molecular outflow associated with G206.93-16.61E2 is also discovered, with arc-like structures indicating a pole-on view.
ASTROPHYSICAL JOURNAL LETTERS
(2023)
Article
Astronomy & Astrophysics
Jiaying Xu, Yi Feng, Di Li, Pei Wang, Yongkun Zhang, Jintao Xie, Huaxi Chen, Han Wang, Zhixuan Kang, Jingjing Hu, Yun Zheng, Chao-Wei Tsai, Xianglei Chen, Dengke Zhou
Summary: This article introduces a database platform called Blinkverse, which is used to collect and analyze dynamic spectra data of fast radio bursts (FRBs). The platform gathers FRB data from various observatories including FAST, CHIME, GBT, Arecibo, and provides convenient access. Users can retrieve FRB data through parameter searches and perform interactive visualization analysis.