Building on the success of the last SCAR AAA meeting held virtually in 2021 and the XXXV SCAR Biennial Meeting Open Science Conference theme (Where the Poles come together), those with interest in either the Arctic or Antarctic research are encouraged to attend.
Astronomy & Astrophysics from Antarctica (AAA) is a Scientific Research Program of SCAR, the Scientific Committee on Antarctic Research. The objectives of AAA are to provide a venue to discuss, promote and coordinate astronomical and astrophysical activities in Antarctica to optimize outcomes from international investments, and to maximize the opportunities for productive interactions with other disciplines.
This is the seventh meeting in the series, following the AAA2011 in Sydney, Australia, the AAA2013 at the Certosa di Pontignano, Italy, the AAA2015 in Hawaii, USA, the AAA2017 in Chiang Mai, Thailand, AAA2019 in the Aosta Valley, Italy, and AAA2021 held remotely hosted by WIPAC at UW-Madison, USA.
Michael Ashley Australia Silvia Masi Italy
Elia Battistelli Italy Wojciech Jacek Miloch Norway
Jennifer Cooper USA Waraporn Nuntiyakul Thailand
XueFei Gong China Zhaohui Shang China
Sven Lidstrom Sweden Delia Tosi USA
Jim Madsen USA Tony Travouillon Australia
A new optical setup, based on the substitution of the secondary and tertiary mirror (M2-M3), will be installed during the Dome C Summer Campaign 2023-2024. These new optics (f/12) have been designed together with the MiR Optomechanical Engineering. The need for a faster focal ratio has been pointed out from the beginning of the activities and moreover after the end of AMICA instrument operations. The sensor evolution reduced the average pixel pitch, hence a shorter focal length is now needed. Together with the mirror set a focal robotized rotator and a focal reducer (0.75X) will be mounted on the ITM Nasmyth focus side B, allowing a wider range of coupling with focal instruments both for Optical and SWIR-IR observations.
A new observational era can finally start from the 800 mm aperture telescope in Dome C, thanks to the new optomechanical system, the major electronics and the SW upgrades: a new INDI-based server, a light but comprehensive telemetry system and a scriptable system for observation robotization are now up and running at the telescope site.
Cryoscope is a 1m scale infrared surveyor planned to carry out transient astronomy and gravitational wave follow up from Dome C. A quarter-size pathfinder is finishing contruction at Caltech and is planned for deployemnt at Dome C to carry out an early survey and retire technical risks of the full sized telescope.
In 2018, the Greenland Telescope (GLT) started scientific observation in Greenland. Since then, we have completed several significant improvements and added new capabilities to the telescope system. This paper presents a full review of the GLT system, a summary of our observation activities since 2018, the lessons learned from the operations in the Arctic regions, and the prospect of the telescope.
Dome A, Antarctica is expected as the best site on earth for infrared observations, due to its cold atmosphere and excellent seeing. We have built two small telescopes as a pathfinder for infrared astronomy at Dome A. The telescopes have diameters of 15 cm, with fields of view of 1.2 square degrees. They are equipped with commercial InGaAs cameras and J/H filters, respectively. They have been installed at Dome A in Jan 2023, and have been observing since then. Here we will report the tests of the telescopes in China, and the preliminary results from Dome A.
The optical properties of dust are central to a wide class of astrophysical objects and the interpretation and modeling of observations, the study of protoplanetary disks being just one example. The development of infrared (IR) astronomy, including observations from Antarctica, will produce a huge amount of data from micron-sized dust, with important implications for radiative transfer processes, which rely on accurate knowledge of the scattering and extinction cross-sections. As is the case in other fields of study, such as atmospheric optics, dust can hardly be described as composed of ideal spheres: the inhomogeneous internal structure affects its radiative properties significantly and hampers the applicability of common approximations. Here we report an analytical, numerical, and experimental study aimed at validating a novel approach to calculate scattering and extinction cross-sections from the two-point density-density correlation function inside the scatterer. Deviations from the commonly used mean-field approximation of up to a factor of 3 are found. The model is closely compared with cross-section measurements and spectrophotometry for the ideal case of well-known colloidal aggregates, which we studied in the visible range, and then extended to the IR range relevant for more general astronomical observations.
The 39th CHINARE returned to Dome A after four years. We maintained the site testing instruments, including seeing monitor KL-DIMM, all-sky camera KLCAM, and multi-layer weather station KLAWS-2G. PLATO-A and the main control and data system for instruments were also serviced. All the unattended instruments are working well and collecting data. We will summarize the field work related to astronomy and discuss a future plan for the site, including how to deal with the snow accumulation. New results will also be reported.
The astronomical seeing is caused by atmospheric turbulence, which is concentrated on the boundary layer. The boundary layer could hardly be avoided even at the best mid-latitude sites, because it is as thick as hundreds of meters from the ground. However, the boundary layer at Dome A, Antarctica could be as thin as ten meters, therefore excellent seeing around 0.3 arcsec is possible to be achieved at Dome A. This was confirmed by the measurements of KunLun Differential Image Motion Monitor (KL-DIMM) in 2019. KL-DIMM was maintained this January, then it was restarted and has been functioning well since then. Here, we will report the seeing results from Dome A in 2023, during both daytime and nighttime. For example, seeing better than 0.15 arcsec lasted for two hours on May 9, with the best seeing of 0.09 arcsec. And we will compare the statistics between the seeing in 2019 and that in 2023, to investigate annual variation. Besides, we will correlate the seeing values with the simultaneous meteorological data from KLAWS. We found a strong correlation between seeing and temperature gradient based on the daytime data in 2019. We will verify if they are correlated during nighttime, consequently, study the formation and evolution of turbulence.
Artist Tristan Duke will share work from his ongoing interdisciplinary, research-based project Glacial Optics. In 2022 the artist undertook an expedition to the arctic where he made functioning camera lenses out of glacier ice, capturing portraits of the glaciers through their own ice. Subsequently the artist has worked with the NSF Ice Core facility and the Wisconsin IceCube Particle Astrophysics Center (WIPAC) to further explore the glacier as a literal and poetic lens through which to understand our world.
This study focuses on neutron monitors (NMs), which are detectors used to measure the flux of high-energy cosmic ray neutrons. The standard NM64 design consists of a reflector, lead rings, a moderator, and a proportional counter filled with boron-10 gas. NMs play a crucial role in studying cosmic rays, their impact on Earth's atmosphere, and space weather. The Changvan neutron monitor undertook round trips between Shanghai and Antarctica, known as a latitude survey. Changvan used a modified design referred to as a “semi-leaded neutron monitor,” with three counters following the NM64 design, but the middle counter lacked lead ring producers. Latitude surveys determine the energy-dependent effective area (yield function) at sea level based on response functions. Monte Carlo simulations were performed to investigate the response functions utilizing atmospheric models of Hobart, Shanghai, and Zhongshan. The primary objective of this study was to compare the Monte Carlo simulations of different atmospheric profiles. This work was supported by NARIT, Chiang Mai University (CMU), and by the NSRF via the Program Management Unit for Human Resources & Institutional Development, Research and Innovation (B39G660028).
Cosmic rays are high-energy particles originating from space, such as the sun, supernova explosions of stars, and other presently unknown sources. The processes governing their formation are not fully understood. The propagation of these particles in the solar wind and Earth's magnetosphere is influenced by magnetic fields. By monitoring variations and fluctuations in cosmic ray intensity, we can study changes in these magnetic fields. Ground-based or sea-based neutron monitors are commonly used to detect atmospheric showers caused by primary cosmic rays with GeV energy range. However, the configurations of neutron detectors may vary, leading to energy-dependent effective areas (yield functions) that are not entirely identical. In our research conducted in Thailand, we have developed portable neutron monitors named “Changvan” and “Thimon.” These instruments enable us to study the energy spectrum of cosmic rays during ocean voyages to and from Antarctica. Our primary focus is to investigate the variations that occur during the typical 11-year sunspot cycle, as well as variations associated with the 22-year solar magnetic cycle. We will discuss the new findings from these voyages and future research approaches. This work is supported in part by NSRF via the Program Management Unit for Human Resources & Institutional Development, Research, and Innovation [grant number B39G660028].
The Antarctica solar coronagraph –AntarctiCor– for the “Extreme Solar Coronagraphy Antarctic Program Experiment” –ESCAPE– comprises an internally-occulted coronagraph based on the externally-occulted ASPIICS space coronagraph for the ESA formation-flying PROBA-3 mission to be launched in 2024.
This presentation describes the AntarctiCor optical design for ground-based observations of the polarized broad-band (591 nm ± 5 nm) K-corona emission from the Italian-French Concordia station, located on the DomeC Antarctica plateau. The science goal of these observations is to map the topology and dynamics of the corona, addressing coronal heating and space weather questions.
The Antarctica plateau of Dome C offers a unique opportunity for ground-based observations of the solar corona, due to the high altitude of the site (3,233 m above sea level), the large amount of the daily hours of observations, and a low-level of sky-brightness background. AntarctiCor was deployed at the Concordia station in four Expeditions funded by the Italian Piano Nazionale Ricerche Antartiche (PNRA): XXXIV (2018-19), XXXV (2019-2020) XXXVII (2021-22) and XXXVIII(2022-23).
This presentation will report the preliminary results of the first coronagraphic observations from Antarctica together with the measurements of the level of sky brightness at Dome C. These measurements have demonstrated that this plateau has indeed a "coronagraphic sky", that is, a sky brightness of the order of 1e-6 of the solar disk brightness.
Some of the lessons learned in operating a solar telescope in Antarctica will also be discussed.
The polar regions have an established history of usage for radio frequency ground stations, offering favourable orbital dynamics for linking with the increasingly large amount of satellites in polar orbits. These dynamics, combined with favourable atmospheric conditions for optics, suggests the Antarctic continent is an excellent location for an optical ground station. We conduct a large number of orbital simulations and combine those results with a suite of remote-sensing data to model the performance of a theoretical optical ground station on Antarctica. Further, we outline the details of an experiment that could be conducted to demonstrate an optical data relay from one of the coastal bases on Antarctica. This concept of a highly effective optical ground station on Antarctica could provide vast improvements to existing bandwidth for offloading science data from the continent as well as offering an effective ground segment for Earth observation satellites.
Measurement of the polarized Cosmic Microwave Background (CMB) over the past few decades has enabled precision probes of the evolutionary history, composition, and dynamics of the primordial Universe. Next-generation CMB experiments will extend this scientific reach, allowing for tests of the inflationary theory of the early Universe, driven through constraints on the tensor-scalar ratio "r" via the search for primordial B-mode polarization. This includes the BICEP Array telescope program, which is targeting observation of B-modes at large angular scales, building on constraints already placed by the BICEP/Keck program. This talk will provide an overview of new infrastructure that is currently in development to ensure the sustainable extension of CMB research at the Amundsen-Scott South Pole Station - notably, the BICEP Array Replacement Tower (BART) project. BART is a straightforward evolution of existing infrastructure at the South Pole aimed at utilizing a limited footprint consistent with heritage facilities to extend experimental cosmology science operations at the South Pole. This discussion will highlight the current status of project design and fabrication, the opportunity for the deployment of a photovoltaic energy system, and plans for future deployment. Finally, the talk will cover the lessons-learned from BART that can be applied to the broader development of polar scientific infrastructure operating at remote, high-altitude, low-temperature sites, in line with current priorities of the global polar science community.
Cost: $155 (included in registration fee)
Pickup at Radisson Blue Polar Hotel
The University of Oslo in Norway has a long tradition in space science research. It started with Kristian Birkeland, one of the pioneers within auroral research, who established first observatories in Northern Norway, on Svalbard and Novaya Zemlaya.
Today, we have participated in large space missions, such as Rosetta, Cluster, BepoColombo, we send our instruments on satellites, launch sounding rocket experiments, and operate instruments in the Arctic and in Antarctica.
In this talk I will present activities and recent highlights related to space science and space weather research at the University of Oslo, with a particular focus on polar regions. I will also put it in a broader context of research in Norway.
The spectrum of the Cosmic Microwave Background (CMB) is remarkably close to a 2.725K blackbody. However, small deviations are expected, due to several interesting pre- and post- recombination phenomena. Here we describe an instrument, the COSmic Monopole Observer (COSMO), aimed at measuring the largest spectral distortion in the 100-300 GHz range using a cryogenic Differential Fourier Transform Spectrometer (DFTS) in Dome-C (Antarctica). The instrument uses fast Kinetic Inductance Detectors and fast atmospheric scans to remove the atmospheric emission and its slow fluctuations. Meanwhile, the DFTS interferogram scan compares the emission from the sky to an accurate internal cryogenic blackbody. Careful control of the temperature of the different instrument components allows to remove unbalanced instrumental emission. The scan strategy has been optimized to cover regions at different Galactic latitudes, to map and remove the emission of interstellar dust. In one year of observations, the instrument is expected to detect the y distortion due to post-recombination ionized matter at 5 sigmas. This project will validate the techonology to be reused in a long duration polar stratospheric balloon flight, to improve significantly the sensitivity taking advantage of the reduced background from the atmosphere and the instrument window. The final goal is to validate the methodology in view of a future ESA Voyage 2050 space mission, which will be able to measure most of the spectral distortions of the CMB monopole.
Observations of the microwave sky enable a vast range of scientific explorations ranging from particle physics and cosmology to astronomy. CMB-S4 is an upcoming ground-based microwave experiment that plans to site telescope at the South Pole in Antarctica as well as in the Atacama desert in Chile. These telescopes will observe the sky with approximately 500,000 superconducting detectors, facilitating an unprecedented leap in experimental sensitivity. The scientific impact of CMB-S4 will include transformative measurements of the cosmic microwave background that inform our understanding of the earliest moments of the Universe. CMB-S4 will also make deep legacy millimeter-wavelength maps covering a large fraction of the sky that will contain galaxy clusters, sub-millimeter galaxies, as well as transient phenomena. In this talk, I will describe the CMB-S4 experiment and highlight some of its many scientific opportunities.
The South Pole provides one of the most pristine sites on Earth for observations of the microwave sky, enabling studies of a host of astrophysical and cosmological phenomena. The South Pole Telescope (SPT), online at Amundsen-Scott South Pole Station since 2007, takes advantage of the stable desert climate to image the sky with unprecedented sensitivity. The third-generation camera, SPT-3G, is composed of over 16,000 polarized superconducting detectors with sensitivity in three microwave frequency bands that bracket the peak emission from the Cosmic Microwave Background (CMB) at 150 GHz. Multi-frequency observations with SPT-3G enable studies of the primordial universe and its evolution via the CMB, as well as characterization of astrophysical sources of microwave emission, such as stars, galaxies and clusters. In this talk, I will review the SPT science program, focusing on recent and upcoming results in cosmology and astrophysics from the SPT-3G camera. I will also describe our observing plans for upcoming seasons, as well as how SPT fits in to the greater cosmology community at the South Pole with the BICEP and CMB-S4 telescope programs.
The theory of cosmological inflation was developed in response to longstanding questions about the origins of our universe. It predicts a specific spectrum of density perturbations that arose during the Big Bang, which has been corroborated by observations of the Cosmic Microwave Background (CMB). This talk will focus on a decisive prediction of inflation that has so far eluded observational confirmation: B-mode polarization of the CMB imprinted by primordial gravitational waves. The BICEP/Keck telescopes target this signature by observing the microwave sky at degree-scale resolution from the South Pole. The intrinsic faintness of the signal, bright Galactic emission at the same observing frequencies, and distortion from gravitational lensing, all contribute to making this measurement extremely challenging. I will explain how the BICEP/Keck program overcomes these experimental challenges, successfully producing world-leading constraints on primordial gravitational waves. As a high-altitude environment with an exceptionally stable atmosphere, the South Pole is the only ground-based site that has allowed such measurements. I will report on the ongoing deployment of the “Stage-3” BICEP Array telescope, which will continue to set limits on inflationary models and probe the early universe. Finally, I will outline how these efforts inform next-generation "Stage-4” experiments, which will also probe the thermal history of our Universe, dark energy and general relativity, and neutrino properties.
SPIDER is a balloon-borne CMB polarimeter that has measured 4.8% of the sky with degree-scale angular resolution. Launching from McMurdo, Antarctica, we benefit from the high altitude and long flights achievable from NASA’s Long Duration Balloon facility, which provides access to space-like observing conditions. Using the data from our first flight in 2015, SPIDER published a constraint on primordial B-modes based on complementary foreground removal techniques: map-based template subtraction; and harmonic-based fitting assuming a modified-blackbody dust model. In this talk, we explore a number of modeling assumptions involved in the spatial and spectral tools developed for the B-mode analysis. After a brief review of the SPIDER experiment and B-mode results, we present preliminary results on the spatial variation of the template-fitting parameter and on the validity of the modified-blackbody dust model. We also present preliminary in-flight performance results from the second flight of SPIDER, which observed the SPIDER region at 95, 150, and 280 GHz. The first-of-their-kind 280 GHz data will help SPIDER and the CMB community better understand dust emission and perform more robust searches for primordial B-modes.
Cosmic microwave background (CMB) photons crossing galaxy clusters
can be scattered by hot electrons in the ionized intracluster medium
(ICM). This results in a small change of the spectrum of the CMB in
the direction of clusters of galaxies. The spectrum of the effect is
characteristic, with a brightness decrease at f < 217 GHz and an
increase at f > 217 GHz, independent of the redshift of the cluster.
This is the thermal Sunyaev-Zeldovich (SZ) effect. Thousands of
clusters have been already detected by means of photometric
measurements of the SZ effect at low frequencies. The motion of the
scatterers produces an additional spectral distortions, with
different shape (kinematic SZ effect).
OLIMPO is a 2.6m aperture mm-wave telescope, working from the
stratosphere at around 150, 250, 350 and 460 GHz to dectect the SZ
effects. At high frequencies, its angular resolution is comparable
to the one of 6-10m aperture ground based telescopes working at low
frequencies. The instrument operates in a pointed mode, so that very
deep observations of specific nearby (z \sim 0.05) clusters can be
obtained, allowing for detailed studies of the density and
temperature distributions of the gas, and of its dynamic state.
The instrument features four arrays of lumped elements kinetic
inductance detectors working at 0.3K, reaching photon-noise limited
performance. For the mainden flight it was launched from the Arctic
airport of Longyearbyen, in 2018. During this technical flight we
succesfully validated for the first time in near space (40 km
altitude) the operation of kinetic inductance detectors arrays, and
the operation of a plug-in differential Fourier Transform
Spectrometer (FTS) for spectral studies within the four wide
observation bands.
In the talk I will review the science goals of OLIMPO, the measured
performance, and the preparation of the payload for the scientific
flight.
Solaris is a scientific and technological project aimed at the development of a smart Solar monitoring system at high radio frequencies based on single-dish imaging techniques (https://sites.google.com/inaf.it/solaris). It combines the implementation of dedicated and interchangeable high-frequency receivers on existing small single-dish radio telescope systems (1.5/2.6m class) available in our laboratories and in Antarctica, to be adapted for Solar observations. Solaris can perform continuous Solar imaging observations nearly 20h/day during Antarctic summer with optimal sky opacity, and it will be the only Solar facility offering continuous monitoring at 100 GHz. In perspective our system could be implemented also in northern hemisphere to offer Solar monitoring for the whole year.
The IceCube Neutrino Observatory is a cubic-kilometer neutrino detector built into the deep glacial ice at the geographic South Pole. Using an array of optical sensors, IceCube detects the Cherenkov light emitted by secondary charged particles produced by neutrino interactions. Following the initial discovery of a diffuse astrophysical neutrino flux a decade ago, recent searches have also identified the blazar TXS 0506+056 and the Seyfert galaxy NGC 1068 as candidate extragalactic neutrino sources. Furthermore, IceCube has recently found evidence for a neutrino flux from our own Galactic plane. We present an overview of IceCube's observations of galactic and extragalactic neutrinos and what these observations may tell us about their sources.
The IceCube Neutrino Observatory is a cubic-kilometer array of 5160 photosensors instrumenting the deep, glacial ice at the geographic South Pole. It detects Cherenkov light emitted by charged particles resulting from neutrino interactions. The spatial and temporal distributions of light in the detector allow to infer the energies and directions of the original neutrinos. As the detector instruments a natural medium, precise in-situ investigations of its optical properties are crucial to the performance of the experiment. This talk will provide an overview over the ice optical modeling. This entails Mie scattering induced by impurities deposited over the past 100'000 years of climate history, undulations of the climate stratigraphy due to the underlying bedrock topology, as well as an anisotropic light propagation along the glacial flow direction resulting from the microscopic crystal structure of the ice.
The Radio Neutrino Observatory - Greenland (RNO-G) is currently under construction in proximity of Summit Station, 3216 m above sea level.
The observatory consists of an array of independent stations, each including both a deep component (with fifteen vertically and horizontally polarized antennas in three 100m-deep boreholes, configured partially as a phased array trigger) and a shallow component (with nine Log-Periodic Dipole Antennas just below the surface, for cosmic ray identification and reconstruction). All the antennas are readout by a central Data Acquisition unit that has been designed and developed to be low noise and low power in the 80-750MHz bandwidth.
Each station is autonomous and relies on a renewable-energy power system and built-in wireless communications to transfer data to Summit station. Currently 7 of 35 planned stations have been installed and are in operation. This talk will review the instrument design, status, and initial performance of these stations and plans to complete the construction of the full RNO-G array.
The IceCube Observatory at the South Pole has detected high energy neutrinos of cosmic origin, including point sources and unresolved Galactic and extragalactic source populations. The extensions to IceCube include the fully funded and under construction low energy, finely segmented extension of the detector (IceCube Upgrade) and a future high energy, high statistics next generation telescope using a mix of optical and radio detectors (Gen2). We will focus on the science impacts of these new detectors along with the hardware and logistics required for their successful construction.