Conveners
A7: Astronomy I
- Peera Pongkitiwanichakul (Mahidol University)
- Maneenate Wechakama (Kasetsart University)
A7: Astronomy I
- Peera Pongkitiwanichakul (Mahidol University)
- Maneenate Wechakama (Kasetsart University)
Most of the matter in the universe is invisible and is known as dark matter (DM). Weakly Interacting Massive Particles (WIMPs) are possible theoretical candidates to explain DM. Hypothetically, WIMPs can be detected indirectly by their annihilation or decay products. A possible product is gamma ray. Many DM profile models predict higher density of WIMPs near the Galactic center. In this work,...
Cosmic rays are high energy particles traveling nearly the speed of light through space. When cosmic rays enter the earth’s atmosphere, they interact with nucleons and start a chain reactions that produce showers of secondary particles, including neutrons, that can reach the surface These neutrons are detected by neutron monitors placed around the globe. The number of neutrons recorded by a...
Aurora phenomenon is an effect of collision between precipitating particles with gyromotion along Earth’s magnetic field and Earth’s ionospheric atoms or molecules. The particles’ precipitation occurs normally around polar regions. However, some auroral particles can reach lower latitude regions when they are highly energetic. A clear emission from Earth’s aurora is mostly from atomic oxygen....
At present, over 3,500 exoplanets have been discovered. In addition to the discovery of new exoplanets, the characterization of planetary atmosphere is a rapidly developing area. One method that is used to study planetary atmosphere is transmission spectroscopy, which measures the variation of transit depth with wavelength. Inflated exoplanets are favorable for transmission spectroscopy, due...
Quasars are a type of AGN with extremely bright luminosities in the optical region of the spectrum which are powered from the accretion process of in-falling matter into the SMBH near the center. This process creates notable features in the AGN spectrum including very broad emission lines which are emitted from the Broad-Line Region (BLR) outside of the SMBH. Although the geometry and the...
Neutron monitors are ground-level detectors of cosmic ray-induced atmospheric secondary particles (mostly neutrons) that are employed world-wide to study variations in the flux of galactic cosmic rays and solar energetic particles in the GeV regime. The neutron monitor standard design (NM64) minimizes detector response to neutrons below $\sim$10 MeV produced by cosmic ray interactions in the...
Proxima Centauri (type – M5.5V, 3050K) is a red dwarf only 4 light yr away, whereas the Sun is type G2V (5780 K). Could oxygenic and/or anoxygenic photosynthesis exist on planet Proxima Centauri b and would we be able to detect it? The light regimes on Earth and Proxima Centauri b are compared to estimate the planet’s suitability for Chlorophyll a (Chl a) and Chl d-based oxygenic...
The launch of the Fermi satellite in 2008 revolutionized gamma-ray pulsar astronomy
by enabling the discovery of many new millisecond pulsars (MSPs). The Fermi
Pulsar Search Consortium (PSC) has organized hundreds of radio observations of
pulsar-like Large Area Telescope (LAT) unassociated sources. Over the past seven
years, the PSC has discovered more than 70 new MSPs,...
Since Einstein’s general relativity or GR cannot explain our universe completely, physicists have tried to find the theory which can describe the dynamic of the universe. One of attempts is modification of GR or modified gravity. We are interested in two models of modified gravity. The first one is the higher dimensional gravity theory which explains the nature by considering GR with extra...
Traversable wormhole or Morris-Thorne wormhole is one of wormholes to which human can travel. However, an exotic matter, the matter with negative pressure, must be included in order to construct such the wormhole. By introducing the cosmological constant into general relativity, it was found that one can minimize the existence of the exotic matter to a thin shell. In this presentation, we...
Synchrotron emission is a good probe for dark matter (DM) particles in the Universe. We search for DM annihilation signals in the Milky Way by using Planck data of synchrotron emission in the microwave bands. We investigate the production of dark matter annihilation into electrons and positrons by studying different channels. We look for upper limits of the mass of dark matter particles on the...
Radial velocity observations for members of the Ori OB1d association in the nebula NGC 1977 were obtained using the MRES spectrograph with the 2.4 m telescope at Thai National Observatory. Radial velocities of 2MASS J05352174-0453118, HD37059, HD294264 are detectable for the first time with a value of 30.02, 32.19 and 60.27 km/s, respectively. Combining the obtained radial velocities from this...
