Salvato in:
| Autori principali: | , , , , , , , , , , , , , , , , , , , , , , , , , |
|---|---|
| Natura: | Preprint |
| Pubblicazione: |
2024
|
| Soggetti: | |
| Accesso online: | https://arxiv.org/abs/2402.15229 |
| Tags: |
Aggiungi Tag
Nessun Tag, puoi essere il primo ad aggiungerne!!
|
| _version_ | 1866914689717370880 |
|---|---|
| author | Aoyagi, M. Bose, R. G. Chun, S. Gau, E. Hu, K. Ishiwata, K. Iyer, N. K. Kislat, F. Kiss, M. Klepper, K. Krawczynski, H. Lisalda, L. Maeda, Y. Malmborg, F. af Matsumoto, H. Miyamoto, A. Miyazawa, T. Pearce, M. Rauch, B. F. Cavero, N. Rodriguez Spooner, S. Takahashi, H. Uchida, Y. West, A. T. Wimalasena, K. Yoshimoto, M. |
| author_facet | Aoyagi, M. Bose, R. G. Chun, S. Gau, E. Hu, K. Ishiwata, K. Iyer, N. K. Kislat, F. Kiss, M. Klepper, K. Krawczynski, H. Lisalda, L. Maeda, Y. Malmborg, F. af Matsumoto, H. Miyamoto, A. Miyazawa, T. Pearce, M. Rauch, B. F. Cavero, N. Rodriguez Spooner, S. Takahashi, H. Uchida, Y. West, A. T. Wimalasena, K. Yoshimoto, M. |
| contents | XL-Calibur is a balloon-borne Compton polarimeter for X-rays in the $\sim$15-80 keV range. Using an X-ray mirror with a 12 m focal length for collecting photons onto a beryllium scattering rod surrounded by CZT detectors, a minimum-detectable polarization as low as $\sim$3% is expected during a 24-hour on-target observation of a 1 Crab source at 45$^{\circ}$ elevation. Systematic effects alter the reconstructed polarization as the mirror focal spot moves across the beryllium scatterer, due to pointing offsets, mechanical misalignment or deformation of the carbon-fiber truss supporting the mirror and the polarimeter. Unaddressed, this can give rise to a spurious polarization signal for an unpolarized flux, or a change in reconstructed polarization fraction and angle for a polarized flux. Using bench-marked Monte-Carlo simulations and an accurate mirror point-spread function characterized at synchrotron beam-lines, systematic effects are quantified, and mitigation strategies discussed. By recalculating the scattering site for a shifted beam, systematic errors can be reduced from several tens of percent to the few-percent level for any shift within the scattering element. The treatment of these systematic effects will be important for any polarimetric instrument where a focused X-ray beam is impinging on a scattering element surrounded by counting detectors. |
| format | Preprint |
| id |
arxiv_https___arxiv_org_abs_2402_15229 |
| institution | arXiv |
| publishDate | 2024 |
| record_format | arxiv |
| spellingShingle | Systematic effects on a Compton polarimeter at the focus of an X-ray mirror Aoyagi, M. Bose, R. G. Chun, S. Gau, E. Hu, K. Ishiwata, K. Iyer, N. K. Kislat, F. Kiss, M. Klepper, K. Krawczynski, H. Lisalda, L. Maeda, Y. Malmborg, F. af Matsumoto, H. Miyamoto, A. Miyazawa, T. Pearce, M. Rauch, B. F. Cavero, N. Rodriguez Spooner, S. Takahashi, H. Uchida, Y. West, A. T. Wimalasena, K. Yoshimoto, M. Instrumentation and Methods for Astrophysics High Energy Astrophysical Phenomena XL-Calibur is a balloon-borne Compton polarimeter for X-rays in the $\sim$15-80 keV range. Using an X-ray mirror with a 12 m focal length for collecting photons onto a beryllium scattering rod surrounded by CZT detectors, a minimum-detectable polarization as low as $\sim$3% is expected during a 24-hour on-target observation of a 1 Crab source at 45$^{\circ}$ elevation. Systematic effects alter the reconstructed polarization as the mirror focal spot moves across the beryllium scatterer, due to pointing offsets, mechanical misalignment or deformation of the carbon-fiber truss supporting the mirror and the polarimeter. Unaddressed, this can give rise to a spurious polarization signal for an unpolarized flux, or a change in reconstructed polarization fraction and angle for a polarized flux. Using bench-marked Monte-Carlo simulations and an accurate mirror point-spread function characterized at synchrotron beam-lines, systematic effects are quantified, and mitigation strategies discussed. By recalculating the scattering site for a shifted beam, systematic errors can be reduced from several tens of percent to the few-percent level for any shift within the scattering element. The treatment of these systematic effects will be important for any polarimetric instrument where a focused X-ray beam is impinging on a scattering element surrounded by counting detectors. |
| title | Systematic effects on a Compton polarimeter at the focus of an X-ray mirror |
| topic | Instrumentation and Methods for Astrophysics High Energy Astrophysical Phenomena |
| url | https://arxiv.org/abs/2402.15229 |