Superconducting transition-edge sensors (TES) carried by X-ray telescopes are powerful tools for the study of neutron stars, black holes and accreting white dwarfs. Our goal is to develop a low-computational-cost technique that optimizes energy and time resolution. TES exhibit a non-linear response with photon energy. Therefore, at low energies we focus on the current-pulse height whereas at high energies we consider the current-pulse width, to retrieve energy and arrival time of X-ray photons. For energies between 0.1 keV and 30 keV and with a sampling rate of 195 kHz, we obtain an energy resolution between 1.32 eV and 2.98 eV.
Measuring distances is crucial in astronomy. Using 2MASS near-infrared photometry and Gaia Data Release 2, we identify carbon stars in the Large Magellanic Clouds (LMC), Small Magellanic Cloud (SMC) and the Milky Way (MW). Carbon stars in the LMC/SMC appear as a distinct horizontal feature in the near-infrared colour-magnitude diagram. We derive the carbon-star luminosity function (CSLF) within a specific colour range. The CSLF will be key in measuring distances to galaxies at 50-60 Mpc and hence estimating a value of the Hubble Constant, thanks to the next generation of telescopes (JWST, ELT, TMT, GMT ).
We identify faint galactic white dwarfs thanks to their colours, in the Canada-France-Hawai‘i Telescope (CFHT) Large Area U-band Deep Survey (CLAUDS). The U-band and optical photometry allows us to fit for the physical properties of the white dwarfs, such as surface temperature, surface gravity, age, mass, and distance. We find a main mass peak consistent with halo and globular-cluster populations. Finally we derive a typical age of the MW stellar halo from our deep field white-dwarf catalogue.
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2023-06-08T11:00:002023-06-08T14:00:00Studies of Evolved Stellar Populations (From Giants to Remnants)Event Information:
Abstract:
Superconducting transition-edge sensors (TES) carried by X-ray telescopes are powerful tools for the study of neutron stars, black holes and accreting white dwarfs. Our goal is to develop a low-computational-cost technique that optimizes energy and time resolution. TES exhibit a non-linear response with photon energy. Therefore, at low energies we focus on the current-pulse height whereas at high energies we consider the current-pulse width, to retrieve energy and arrival time of X-ray photons. For energies between 0.1 keV and 30 keV and with a sampling rate of 195 kHz, we obtain an energy resolution between 1.32 eV and 2.98 eV.
Measuring distances is crucial in astronomy. Using 2MASS near-infrared photometry and Gaia Data Release 2, we identify carbon stars in the Large Magellanic Clouds (LMC), Small Magellanic Cloud (SMC) and the Milky Way (MW). Carbon stars in the LMC/SMC appear as a distinct horizontal feature in the near-infrared colour-magnitude diagram. We derive the carbon-star luminosity function (CSLF) within a specific colour range. The CSLF will be key in measuring distances to galaxies at 50-60 Mpc and hence estimating a value of the Hubble Constant, thanks to the next generation of telescopes (JWST, ELT, TMT, GMT ).
We identify faint galactic white dwarfs thanks to their colours, in the Canada-France-Hawai‘i Telescope (CFHT) Large Area U-band Deep Survey (CLAUDS). The U-band and optical photometry allows us to fit for the physical properties of the white dwarfs, such as surface temperature, surface gravity, age, mass, and distance. We find a main mass peak consistent with halo and globular-cluster populations. Finally we derive a typical age of the MW stellar halo from our deep field white-dwarf catalogue.
Event Location:
HENN 302