arXiv subjects

Jompoj Wongphechauxsorn

Publications and source records attributed to Jompoj Wongphechauxsorn.

4 recordsLinked to original sources

arXiv2026

The Wetterstein Millimeter Telescope: A New German Facility for Astronomy and Geodesy

The Wetterstein Millimeter Telescope (WMT) is a planned broadband (1.2-120 GHz) radio telescope to be established near the Environmental Research Station Schneefernerhaus (UFS) on Germany's highest mountain, the Zugspitze. Developed by a consortium of German research institutes and partners, the WMT is conceived as a multidisciplinary research infrastructure supporting radio astronomy, geodetic VLBI, satellite communications, space situational awareness, and technology development. The telescope is designed to operate within international VLBI networks, including the European VLBI Network, the Global mm-VLBI Array, and future ngVLA and SKA-VLBI observations. This contribution summarizes recent progress in the WMT project, including the evolution of the antenna design, and highlights the potential of the WMT to support future astronomical and geodetic VLBI.

astro-ph.IM↗

arXiv2026

VLBI with SKAMPI, the SKA-Mid MPIfR dish demonstrator

The SKA-MPIfR telescope (SKAMPI) is a prototype SKA-Mid antenna located at the SKA site in the Karoo Desert, South Africa. It is funded by the Max Planck Society, through the Max Planck Institute for Radio Astronomy (MPIfR), and operated in collaboration with the South African Radio Astronomy Observatory (SARAO). The first fringe-finding experiments have been conducted with the European VLBI Network and the southern hemisphere Long Baseline Array, connecting SKAMPI with Europe and Australia. Here we present early SKAMPI VLBI mode results in S-Band, including successful fringe detections and evaluating the integration and imaging performances of SKAMPI in observations with the EVN, LBA, and VLBA.

astro-ph.IM↗

arXiv2026

Extending the SKA Across Africa: The Case for a Continental African VLBI Network

The African continent holds the key to unlocking the full potential of global Very Long Baseline Interferometry (VLBI). Strategic placement of radio telescopes across Africa provides the crucial north-south and intermediate baselines that are currently missing from the global VLBI network. This expansion will dramatically enhance imaging fidelity and resolution. In this chapter, we propose a vision for a continental African VLBI Network (AVN) that will operate in close synergy with SKA-Mid, enabling transformational science across all cosmic scales. While only the Hartebeesthoek Radio Astronomy Observatory (HartRAO) in South Africa and the Ghana Radio Astronomy Observatory (GRAO) are currently operational, several partner countries are in the process of refurbishing or converting existing antennas. Here, we advocate for the expansion of this network through the deployment of a limited number of SKA-Mid-type telescopes across the continent, creating an "African arm" of SKA-VLBI. With a maximum baseline of ~ 9000 km (from Rabat, Morocco to Cassis, Mauritius), the proposed continental facility will surpass for example, the resolution that will be achieved by the next generation Very Large Array (ngVLA) by ~ 10 % at similar observing frequencies and significantly enhance global VLBI coverage. Beyond the scientific and technical gains, the AVN represents a unique opportunity for sustainable growth in human capital, education, and innovation across Africa. Developing and operating a continental VLBI array will train the next generation of engineers, data scientists, and astronomers, stimulate local industry, and inspire public engagement in science and technology. We outline the current status, challenges, and potential roadmap towards realizing this vision, and we highlight how a continental African VLBI network will position Africa at the forefront of global radio astronomy.

astro-ph.IM↗

arXiv2023

A search for pulsars around Sgr A* in the first Event Horizon Telescope dataset

The Event Horizon Telescope (EHT) observed in 2017 the supermassive black hole at the center of the Milky Way, Sagittarius A* (Sgr A*), at a frequency of 228.1 GHz ($λ$=1.3 mm). The fundamental physics tests that even a single pulsar orbiting Sgr A* would enable motivate searching for pulsars in EHT datasets. The high observing frequency means that pulsars - which typically exhibit steep emission spectra - are expected to be very faint. However, it also negates pulse scattering, an effect that could hinder pulsar detections in the Galactic Center. Additionally, magnetars or a secondary inverse Compton emission could be stronger at millimeter wavelengths than at lower frequencies. We present a search for pulsars close to Sgr A* using the data from the three most-sensitive stations in the EHT 2017 campaign: the Atacama Large Millimeter/submillimeter Array, the Large Millimeter Telescope and the IRAM 30 m Telescope. We apply three detection methods based on Fourier-domain analysis, the Fast-Folding-Algorithm and single pulse search targeting both pulsars and burst-like transient emission; using the simultaneity of the observations to confirm potential candidates. No new pulsars or significant bursts were found. Being the first pulsar search ever carried out at such high radio frequencies, we detail our analysis methods and give a detailed estimation of the sensitivity of the search. We conclude that the EHT 2017 observations are only sensitive to a small fraction ($\lesssim$2.2%) of the pulsars that may exist close to Sgr A*, motivating further searches for fainter pulsars in the region.

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