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Related papers: High-frequency oscillations in small chromospheric…

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We present joint observations of the Sun by the Atacama Large Millimeter/submillimeter Array (ALMA) and the Interface Region Imaging Spectrograph (IRIS). The observations were made of a solar active region on 2015 December 18 as part of the…

Solar and Stellar Astrophysics · Physics 2017-08-30 T. S. Bastian , G. Chintzoglou , B. De Pontieu , M. Shimojo , D. Schmit , J. Leenaarts , M. Loukitcheva

We report serendipitous detections of line emission with the Atacama Large Millimeter/submillimeter Array (ALMA) in band 3, 6, and 7 in the central parsec down to within 1" around Sgr A* at an up to now highest resolution (<0.5") view of…

Variability of pre-main-sequence stars observed at optical wavelengths has been attributed tofluctuations in the mass accretion rate from the circumstellar disk onto the forming star.Detailed models of accretion disks suggest that young…

Solar and Stellar Astrophysics · Physics 2019-02-05 Logan Francis , Doug Johnstone , Michael M. Dunham , Todd R. Hunter , Steve Mairs

The Atacama Large Millimeter/submillimeter Array (ALMA) is an international radio telescope under construction in the Atacama Desert of northern Chile. ALMA is situated on a dry site at 5000 m elevation, allowing excellent atmospheric…

Instrumentation and Methods for Astrophysics · Physics 2015-05-13 Alwyn Wootten , A. Richard Thompson

By observing bright and compact astronomical sources while also taking data with the 183 GHz Water Vapour Radiometers, ALMA will be able to measure the `empirical' relationship between fluctuations in the phase of the astronomical signal…

Instrumentation and Methods for Astrophysics · Physics 2009-07-28 Bojan Nikolic

Solar chromospheric observations of sunspot umbrae offer an exceptional view of magneto-hydrodynamic wave phenomena. In recent years, a wealth of wave signatures related to propagating magneto-acoustic modes have been presented, which…

We present observations of transverse oscillations in slender Ca II H fibrils (SCFs) in the lower solar chromosphere. We use a 1 hr long time series of high- (spatial and temporal-) resolution seeing-free observations in a 0.11 nm wide…

Three-minute oscillations are a common phenomenon in the solar chromosphere above a sunspot. Oscillations can be affected by the energy release process related to solar flares. In this paper, we report on an enhanced oscillation in flare…

Solar and Stellar Astrophysics · Physics 2023-11-30 Ya Wang , Lyndsay Fletcher , Sargam Mulay , Haisheng Ji , Wenda Cao

We report here Atacama Large Millimeter/submillimeter Array (ALMA) N$_2$H$^+$ (1-0) images of the Orion Molecular Cloud 2 and 3 (OMC-2/3) with high angular resolution (3'' or 1200 au) and high spatial dynamic range. Combining dataset from…

Astrophysics of Galaxies · Physics 2021-02-10 Nannan Yue , Di Li , Qizhou Zhang , Lei Zhu , Jonathan Henshaw , Diego Mardones , Zhiyuan Ren

The solar chromosphere is heated to temperatures higher than predicted by radiative equilibrium. This excess heating is greater in active regions where the magnetic field is stronger. We aim to investigate the magnetic topology associated…

Solar and Stellar Astrophysics · Physics 2022-05-04 J. M. da Silva Santos , S. Danilovic , J. Leenaarts , J. de la Cruz Rodríguez , X. Zhu , S. M. White , G. J. M. Vissers , M. Rempel

Waves are thought to play a significant role in the heating of the solar atmosphere and the acceleration of the wind. Among the many types of waves observed in the Sun, the so-called p-modes with a 3 mHz frequency peak dominate the lower…

We study chromospheric oscillations including umbral flashes and running penumbral waves in a sunspot of active region (AR) using scanning spectroscopy in H-alpha and Ca II 8542A, with the Fast Imaging Solar Spectrograph (FISS) at the 1.6…

Solar and Stellar Astrophysics · Physics 2013-02-07 Ram Ajor Maurya , Jongchul Chae , Hyungmin Park , Heesu Yang , Donguk Song , Kyuhyoun Cho

The lensing power spectra for gravitational potential, astrometric shift, and convergence perturbations are powerful probes to investigate dark matter structures on small scales. We report the first lower and upper bounds of these lensing…

Cosmology and Nongalactic Astrophysics · Physics 2023-09-18 Kaiki Taro Inoue , Takeo Minezaki , Satoki Matsushita , Koichiro Nakanishi

In the earliest (so-called "Class 0") phase of sunlike (low-mass) star formation, circumstellar disks are expected to form, feeding the protostars. However, such disks are difficult to resolve spatially because of their small sizes.…

Astrophysics of Galaxies · Physics 2017-05-01 Chin-Fei Lee , Zhi-Yun Li , Paul. T. P Ho , Naomi Hirano , Qizhou Zhang , Hsien Shang

Millimeter/submillimeter variability is often attributed to dynamical disk-mediated accretion, yet detection is limited to low-mass protostars in nearby clouds. Recent observations have also revealed significant (sub)millimeter variability…

Small-scale magnetic fields are thought to play an important role in the heating of the outer solar atmosphere. By taking advantage of the unprecedented high-spatial and temporal cadence of IMaX, the filter vector polarimeter on board the…

Solar and Stellar Astrophysics · Physics 2015-06-15 M. Stangalini , S. K. Solanki , R. Cameron , V. Martìnez Pillet

We present a multi-wavelength analysis of five submillimeter sources (S_1.1mm = 0.54-2.02 mJy) that were detected during our 1.1-mm-deep continuum survey in the SXDF-UDS-CANDELS field (2 arcmin^2, 1sigma = 0.055 mJy beam^-1) using the…

We present a new catalogue of ALMA observations of 3,364 bright, compact radio sources, mostly blazars, used as calibrators. These sources were observed between May 2011 and July 2018, for a total of 47,115 pointings in different bands and…

Astrophysics of Galaxies · Physics 2019-02-20 M. Bonato , E. Liuzzo , D. Herranz , J. Gonzalez-Nuevo , L. Bonavera , M. Tucci , M. Massardi , G. De Zotti , M. Negrello , M. A. Zwaan

The short-lived ionized emission lines in early spectroscopy of the nearby type II supernova SN 2024ggi signify the presence of dense circumstellar matter (CSM) close to its progenitor star. We proposed the Atacama Large…

Solar and Stellar Astrophysics · Physics 2024-12-31 Maokai Hu , Yiping Ao , Yi Yang , Lei Hu , Fulin Li , Lifan Wang , Xiaofeng Wang