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Abnormal Stokes V profiles observed by Hinode in a sunspot: Detection of hidden photospheric fine-structures
Rezaei, R.; Hamedivafa, H.
Context. Hidden magnetic components in a sunspot are present as small-scale structures that are absent in low-resolution observations. Aims. We search for traces of the hidden magnetic components in spectro-polarimetric observations of a mature sunspot close to the disk center recorded by Hinode. Methods. To find extra humps in the far blue and re…
Low-resolution transit spectroscopy of three hot Jupiters using the 2 m Himalayan Chandra Telescope
Sivarani, Thirupathi; Oza, Apurva V.; Goyal, Jayesh +3 more
Here, we present the low-resolution transmission spectroscopy of three giant planets using the Himalayan Faint Object Spectrograph Camera (HFOSC) on the 2 m Himalayan Chandra Telescope (HCT) in Hanle, India. It is the first application of transmission spectroscopy with HCT. This study presents results from a single transit, each for three planets:…
The return of FarNet-II: Generation of solar far-side magnetograms from helioseismic data
Asensio Ramos, A.; Felipe, T.; Broock, E. G.
Context. The far-side activity of the Sun can be inferred by interpreting the near-side wave field using local helioseismic techniques. However, detections are limited to strongly active regions because signal-to-noise ratio of the data is low. Recently, we developed the FarNet and FarNet-II neural networks to improve the identification of active …
CHIMPS2: 13CO J = 3→2 emission in the central molecular zone
Moore, T. J. T.; Rigby, A. J.; Longmore, S. N. +12 more
We present the initial data for the $(J = 3 \rightarrow 2)$ transition of $^{13}\text{CO}$ obtained from the central molecular zone (CMZ) of the Milky Way as part of the CO Heterodyne Inner Milky Way Plane Survey 2 (CHIMPS2). Covering $359^{\circ } \le l \le 1^{\circ }$ and $|b| \le 0.5^{\circ }$ with an angular resolution of 19 arcsec, velocity r…
VLBI with SKA: Possible Arrays and Astrometric Science
Xu, Ye; Liu, Dejian; Hao, Chaojie +4 more
The next generation of very long baseline interferometry (VLBI) is stepping into the era of microarcsecond (µas) astronomy, and pushing astronomy, especially astrometry, to new heights. VLBI with the Square Kilometre Array (SKA), SKA-VLBI, will increase current sensitivity by an order of magnitude, and reach astrometric precision routinely b…
Study of Nonlinear Evolution of Spacetime Fluctuations in Quantum Gravity Inflation for Deriving Primordial Spectrum
Hamada, Ken-ji
We study the evolution of quantum fluctuations of gravity around an inflationary solution in renormalizable quantum gravity, in which the initial scalar-fluctuation dominance is shown by the background-free nature expressed by a special conformal invariance. Inflation ignites at the Planck scale and continues until spacetime phase transition occur…
The Kinematic and Chemical Properties of the Close-in Planet Host Star 8 UMi
Wang, Wei; Huang, Yang; Beers, Timothy C. +11 more
A recent study by Hon et al. reported that a close-in planet around the red clump star, 8 UMi, should have been engulfed during the expansion phase of its parent star's evolution. They explained the survival of this exoplanet through a binary-merger channel for 8 UMi. The key to testing this formation scenario is to derive the true age of this sta…
Spectroscopic observations of selected planetary nebulae from the HASH data base
Temiz, Utkan; Aksaker, Nazım; Akyuz, Aysun
We conducted research on the classification and physical properties of 10 objects from the HASH [Hong Kong/Australian Astronomical Observatory/Strasbourg Observatory H-alpha Planetary Nebula (PN)] data base with small angular sizes (<8 arcsec) in the Northern hemisphere. The sample consisted of six Likely PNe, two new candidates, one emission-l…
The solar wind heavy ion composition in the ascending phases of the solar cycles 23 and 25
Livi, S.; Galvin, A. B.; Kistler, L. M. +5 more
The approximately 11-year solar cycle has been shown to impact the heavy ion composition of the solar wind, even when accounting for streams of differing speeds; however, the heavy ion composition observed between the same specific phases of a past solar cycle and the current cycle has rarely, if ever, been compared. Here, we compare the heavy ion…
Long-term monitoring of the Oe star VES 735: Ope! not so quiet after all
Kerton, C. R.; Marshall, Brandon
Only 3-4 per cent of Galactic O stars are observed to display the emission features representative of the OBe phenomenon, compared to Galactic B stars, which display these characteristics in 25-35 per cent of B0 and B1 stars. We present new observations of the high-mass O star, VES 735, which confirms its classification as one of these rare emissi…