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51. HERA Phase I Limits on the Cosmic 21-cm Signal: Constraints on Astrophysics and Cosmology During the Epoch of Reionization

Author: The HERA Collaboration, Abdurashidova, Zara, Aguirre, James E., Alexander, Paul, Ali, Zaki, Balfour, Yanga, Barkana, Rennan, Beardsley, Adam, Bernardi, Gianni, Billings, Tashalee, Bowman, Judd, Bradley, Richard, Bull, Phillip, Burba, Jacob, Carey, Steven, Carilli, Christopher, Cheng, Carina, DeBoer, David, Dexter, Matthew, Acedo, Eloy de Lera, Dillon, Joshua, Ely, John, Ewall-Wice, Aaron, Fagnoni, Nicolas, Fialkov, Anastasia, Fritz, Randall, Furlanetto, Steven, Gale-Sides, Kingsley, Glendenning, Brian, Gorthi, Deepthi, Greig, Bradley, Grobbelaar, Jasper, Halday, Ziyaad, Hazelton, Bryna, Heimersheim, Stefan, Hewitt, Jacqueline, Hickish, Jack, Jacobs, Daniel, Julius, Austin, Kern, Nicholas, Kerrigan, Joshua, Kittiwisit, Piyanat, Kohn, Saul, Kolopanis, Matthew, Lanman, Adam, La Plante, Paul, Lekalake, Telalo, Lewis, David, Liu, Adrian, Ma, Yin-Zhe, MacMahon, David, Malan, Lourence, Malgas, Cresshim, Maree, Matthys, Martinot, Zachary, Matsetela, Eunice, Mesinger, Andrei, Mirocha, Jordan, Molewa, Mathakane, Morales, Miguel, Mosiane, Tshegofalang, Munoz, Julian, Murray, Steven, Neben, Abraham, Nikolic, Bojan, Nunhokee, Chuneeta Devi, Parsons, Aaron, Patra, Nipanjana, Pieterse, Samantha, Pober, Jonathan, Qin, Yuxiang, Razavi-Ghods, N., Reis, Itamar, Ringuette, Jon, Robnett, James, Rosie, Kathryn, Santos, Mario, Sikder, Sudipta, Sims, Peter, Smith, Craig, Syce, Angelo, Thyagarajan, Nithyanandan, Williams, Peter, and Zheng, Haoxuan
Subjects: Astrophysics - Cosmology and Nongalactic Astrophysics, Astrophysics - Astrophysics of Galaxies, High Energy Physics - Theory
Abstract: Recently, the Hydrogen Epoch of Reionization Array (HERA) collaboration has produced the experiment's first upper limits on the power spectrum of 21-cm fluctuations at z~8 and 10. Here, we use several independent theoretical models to infer constraints on the intergalactic medium (IGM) and galaxies during the epoch of reionization (EoR) from these limits. We find that the IGM must have been heated above the adiabatic cooling threshold by z~8, independent of uncertainties about the IGM ionization state and the nature of the radio background. Combining HERA limits with galaxy and EoR observations constrains the spin temperature of the z~8 neutral IGM to 27 K < T_S < 630 K (2.3 K < T_S < 640 K) at 68% (95%) confidence. They therefore also place a lower bound on X-ray heating, a previously unconstrained aspects of early galaxies. For example, if the CMB dominates the z~8 radio background, the new HERA limits imply that the first galaxies produced X-rays more efficiently than local ones (with soft band X-ray luminosities per star formation rate constrained to L_X/SFR = { 10^40.2, 10^41.9 } erg/s/(M_sun/yr) at 68% confidence), consistent with expectations of X-ray binaries in low-metallicity environments. The z~10 limits require even earlier heating if dark-matter interactions (e.g., through millicharges) cool down the hydrogen gas. Using a model in which an extra radio background is produced by galaxies, we rule out (at 95% confidence) the combination of high radio and low X-ray luminosities of L_{r,\nu}/SFR > 3.9 x 10^24 W/Hz/(M_sun/yr) and L_X/SFR<10^40 erg/s/(M_sun/yr). The new HERA upper limits neither support nor disfavor a cosmological interpretation of the recent EDGES detection. The analysis framework described here provides a foundation for the interpretation of future HERA results., Comment: 40 pages, 19 figures, accepted to ApJ
Published: 2021
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52. Combined sensitivity of JUNO and KM3NeT/ORCA to the neutrino mass ordering

Author: KM3NeT Collaboration, Aiello, S., Albert, A., Alshamsi, M., Garre, S. Alves, Aly, Z., Ambrosone, A., Ameli, F., Andre, M., Androulakis, G., Anghinolfi, M., Anguita, M., Ardid, M., Ardid, S., Aublin, J., Bagatelas, C., Baret, B., Pree, S. Basegmez du, Bendahman, M., Benfenati, F., Berbee, E., Berg, A. M. van den, Bertin, V., Biagi, S., Boettcher, M., Cabo, M. Bou, Boumaaza, J., Bouta, M., Bouwhuis, M., Bozza, C., Brânzaş, H., Bruijn, R., Brunner, J., Bruno, R., Buis, E., Buompane, R., Busto, J., Caiffi, B., Calvo, D., Campion, S., Capone, A., Carretero, V., Castaldi, P., Celli, S., Chabab, M., Chau, N., Chen, A., Cherubini, S., Chiarella, V., Chiarusi, T., Circella, M., Cocimano, R., Coelho, J. A. B., Coleiro, A., Molla, M. Colomer, Coniglione, R., Coyle, P., Creusot, A., Cruz, A., Cuttone, G., Dallier, R., De Martino, B., Di Palma, I., Díaz, A. F., Diego-Tortosa, D., Distefano, C., Domi, A., Donzaud, C., Dornic, D., Dörr, M., Drouhin, D., Eberl, T., Eddyamoui, A., van Eeden, T., van Eijk, D., Bojaddaini, I. El, Enzenhöfer, A., Espinosa, V., Fermani, P., Ferrara, G., Filipovic, M. D., Filippini, F., Fusco, L. A., Gal, T., Méndez, J. García, Soto, A. Garcia, Garufi, F., Gatelet, Y., Gatius, C., Geisselbrecht, N., Gialanella, L., Giorgio, E., Gozzini, S. R., Gracia, R., Graf, K., Grella, G., Guderian, D., Guidi, C., Guillon, B., Gutiérrez, M., Haefner, J., Hallmann, S., Hamdaoui, H., van Haren, H., Heijboer, A., Hekalo, A., Hennig, L., Hernández-Rey, J. J., Hofestädt, J., Huang, F., Ibnsalih, W. Idrissi, Illuminati, G., James, C. W., de Jong, M., de Jong, P., Jung, B. J., Kalaczynski, P., Kalekin, O., Katz, U. F., Chowdhury, N. R. Khan, Kistauri, G., van der Knaap, F., Kooijman, P., Kouchner, A., Kulikovskiy, V., Labalme, M., Lahmann, R., Lamoureux, M., Larosa, G., Lastoria, C., Lazo, A., Breton, R. Le, Stum, S. Le, Lehaut, G., Leonardi, O., Leone, F., Leonora, E., Lessing, N., Levi, G., Lincetto, M., Clark, M. Lindsey, Lipreau, T., Alvarez, C. Llorens, Longhitano, F., Lopez-Coto, D., Lygda, A., Maderer, L., Majumdar, J., Mańczak, J., Margiotta, A., Marinelli, A., Markou, C., Martin, L., Martínez-Mora, J. A., Martini, A., Marzaioli, F., Mastroianni, S., Melis, K. W., Miele, G., Migliozzi, P., Migneco, E., Mijakowski, P., Miranda, L. S., Mollo, C. M., Moser, M., Moussa, A., Muller, R., Musumeci, M., Nauta, L., Navas, S., Nicolau, C. A., Nkosi, B., Fearraigh, B. Ó, O'Sullivan, M., Organokov, M., Orlando, A., González, J. Palacios, Papalashvili, G., Papaleo, R., Păun, A. M., Păvălaş, G. E., Pellegrino, C., Perrin-Terrin, M., Pestel, V., Piattelli, P., Pieterse, C., Pisanti, O., Poirè, C., Popa, V., Pradier, T., Probst, I., Pulvirenti, S., Quéméner, G., Randazzo, N., Razzaque, S., Real, D., Reck, S., Riccobene, G., Romanov, A., Rovelli, A., Greus, F. Salesa, Samtleben, D. F. E., Losa, A. Sánchez, Sanguineti, M., Santonocito, D., Sapienza, P., Schnabel, J., Schneider, M. F., Schumann, J., Schutte, H. M., Seneca, J., Sgura, I., Shanidze, R., Sharma, A., Sinopoulou, A., Spisso, B., Spurio, M., Stavropoulos, D., Stellacci, S. M., Taiuti, M., Tayalati, Y., Thiersen, H., Tingay, S., Tsagkli, S., Tsourapis, V., Tzamariudaki, E., Tzanetatos, D., Van Elewyck, V., Vasileiadis, G., Versari, F., Vivolo, D., de Wasseige, G., Wilms, J., Wojaczyński, R., de Wolf, E., Yousfi, T., Zavatarelli, S., Zegarelli, A., Zito, D., Zornoza, J. D., Zúñiga, J., Zywucka, N., members, JUNO Collaboration, Ahmad, S., de André, J. P. A. M., Baussan, E., Bordereau, C., Cabrera, A., Cerna, C., Donchenko, G., Doroshkevich, E. A., Dracos, M., Druillole, F., Jollet, C., Kalousis, L. N., Kampmann, P., Kouzakov, K., Lokhov, A., Lubsandorzhiev, B. K., Lubsandorzhiev, S. B., Meregaglia, A., Miramonti, L., Perrot, F., Rico, L. F. Piñeres, Popov, A., Rasheed, R., Settimo, M., Stankevich, K., Steiger, H., Stock, M. R., Studenikin, A., Triossi, A., Trzaska, W., Vialkov, M., Wonsak, B., Wurtz, J., and Yermia, F.
Subjects: High Energy Physics - Experiment, High Energy Physics - Phenomenology
Abstract: This article presents the potential of a combined analysis of the JUNO and KM3NeT/ORCA experiments to determine the neutrino mass ordering. This combination is particularly interesting as it significantly boosts the potential of either detector, beyond simply adding their neutrino mass ordering sensitivities, by removing a degeneracy in the determination of $\Delta m_{31}^2$ between the two experiments when assuming the wrong ordering. The study is based on the latest projected performances for JUNO, and on simulation tools using a full Monte Carlo approach to the KM3NeT/ORCA response with a careful assessment of its energy systematics. From this analysis, a $5\sigma$ determination of the neutrino mass ordering is expected after 6 years of joint data taking for any value of the oscillation parameters. This sensitivity would be achieved after only 2 years of joint data taking assuming the current global best-fit values for those parameters for normal ordering., Comment: 24 pages, 9 figures
Published: 2021
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53. First Results from HERA Phase I: Upper Limits on the Epoch of Reionization 21 cm Power Spectrum

Author: The HERA Collaboration, Abdurashidova, Zara, Aguirre, James E., Alexander, Paul, Ali, Zaki S., Balfour, Yanga, Beardsley, Adam P., Bernardi, Gianni, Billings, Tashalee S., Bowman, Judd D., Bradley, Richard F., Bull, Philip, Burba, Jacob, Carey, Steve, Carilli, Chris L., Cheng, Carina, DeBoer, David R., Dexter, Matt, Acedo, Eloy de Lera, Dibblee-Barkman, Taylor, Dillon, Joshua S., Ely, John, Ewall-Wice, Aaron, Fagnoni, Nicolas, Fritz, Randall, Furlanetto, Steven R., Gale-Sides, Kingsley, Glendenning, Brian, Gorthi, Deepthi, Greig, Bradley, Grobbelaar, Jasper, Halday, Ziyaad, Hazelton, Bryna J., Hewitt, Jacqueline N., Hickish, Jack, Jacobs, Daniel C., Julius, Austin, Kern, Nicholas S., Kerrigan, Joshua, Kittiwisit, Piyanat, Kohn, Saul A., Kolopanis, Matthew, Lanman, Adam, La Plante, Paul, Lekalake, Telalo, Lewis, David, Liu, Adrian, MacMahon, David, Malan, Lourence, Malgas, Cresshim, Maree, Matthys, Martinot, Zachary E., Matsetela, Eunice, Mesinger, Andrei, Molewa, Mathakane, Morales, Miguel F., Mosiane, Tshegofalang, Murray, Steven G., Neben, Abraham R., Nikolic, Bojan, Nunhokee, Chuneeta D., Parsons, Aaron R., Patra, Nipanjana, Pascua, Robert, Pieterse, Samantha, Pober, Jonathan C., Razavi-Ghods, Nima, Ringuette, Jon, Robnett, James, Rosie, Kathryn, Sims, Peter, Singh, Saurabh, Smith, Craig, Syce, Angelo, Thyagarajan, Nithyanandan, Williams, Peter K. G., and Zheng, Haoxuan
Subjects: Astrophysics - Cosmology and Nongalactic Astrophysics, Astrophysics - Astrophysics of Galaxies
Abstract: We report upper-limits on the Epoch of Reionization (EoR) 21 cm power spectrum at redshifts 7.9 and 10.4 with 18 nights of data ($\sim36$ hours of integration) from Phase I of the Hydrogen Epoch of Reionization Array (HERA). The Phase I data show evidence for systematics that can be largely suppressed with systematic models down to a dynamic range of $\sim10^9$ with respect to the peak foreground power. This yields a 95% confidence upper limit on the 21 cm power spectrum of $\Delta^2_{21} \le (30.76)^2\ {\rm mK}^2$ at $k=0.192\ h\ {\rm Mpc}^{-1}$ at $z=7.9$, and also $\Delta^2_{21} \le (95.74)^2\ {\rm mK}^2$ at $k=0.256\ h\ {\rm Mpc}^{-1}$ at $z=10.4$. At $z=7.9$, these limits are the most sensitive to-date by over an order of magnitude. While we find evidence for residual systematics at low line-of-sight Fourier $k_\parallel$ modes, at high $k_\parallel$ modes we find our data to be largely consistent with thermal noise, an indicator that the system could benefit from deeper integrations. The observed systematics could be due to radio frequency interference, cable sub-reflections, or residual instrumental cross-coupling, and warrant further study. This analysis emphasizes algorithms that have minimal inherent signal loss, although we do perform a careful accounting in a companion paper of the small forms of loss or bias associated with the pipeline. Overall, these results are a promising first step in the development of a tuned, instrument-specific analysis pipeline for HERA, particularly as Phase II construction is completed en route to reaching the full sensitivity of the experiment., Comment: Accepted to ApJ. https://reionization.org/science/public-data-release-1/
Published: 2021
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54. Studying Bioluminescence Flashes with the ANTARES Deep Sea Neutrino Telescope

Author: Reeb, N., Hutschenreuter, S., Zehetner, P., Ensslin, T., Alves, S., André, M., Anghinolfi, M., Anton, G., Ardid, M., Aubert, J. -J., Aublin, J., Baret, B., Basa, S., Belhorma, B., Bendahman, M., Bertin, V., Biagi, S., Bissinger, M., Boumaaza, J., Bouta, M., Bouwhuis, M. C., Brânzaş, H., Bruijn, R., Brunner, J., Busto, J., Caiffi, B., Capone, A., Caramete, L., Carr, J., Carretero, V., Celli, S., Chabab, M., Chau, T. N., Moursli, R. Cherkaoui El, Chiarusi, T., Circella, M., Coleiro, A., Colomer-Molla, M., Coniglione, R., Coyle, P., Creusot, A., Díaz, A. F., de Wasseige, G., Deschamps, A., Distefano, C., Di Palma, I., Domi, A., Donzaud, C., Dornic, D., Drouhin, D., Eberl, T., van Eeden, T., Khayati, N. El, Enzenhöfer, A., Fermani, P., Ferrara, G., Filippini, F., Fusco, L., Gatelet, Y., Gay, P., Glotin, H., Gozzini, R., Ruiz, R. Gracia, Graf, K., Guidi, C., Hallmann, S., van Haren, H., Heijboer, A. J., Hello, Y., Hernández-Rey, J. J., Hößl, J., Hofestädt, J., Huang, F., Illuminati, G., James, C. W., Jisse-Jung, B., Jong, M. d., Jong, P. d., Jongen, M., Kadler, M., Kalekin, O., Katz, U., Khan-Chowdhury, N. R., Kouchner, A., Kreykenbohm, I., Kulikovskiy, V., Lahmann, R., Breton, R. Le, Lefèvre, D., Leonora, E., Levi, G., Lincetto, M., Lopez-Coto, D., Loucatos, S., Maderer, L., Manczak, J., Marcelin, M., Margiotta, A., Marinelli, A., Martínez-Mora, J. A., Melis, K., Migliozzi, P., Moussa, A., Muller, R., Nauta, L., Navas, S., Nezri, E., Fearraigh, B. Ó, Organokov, M., Păvălaş, G. E., Pellegrino, C., Perrin-Terrin, M., Piattelli, P., Pieterse, C., Poirè, C., Popa, V., Pradier, T., Randazzo, N., Reck, S., Riccobene, G., Romanov, A., Sánchez-Losa, A., Greus, F. Salesa, Samtleben, D. F. E., Sanguineti, M., Sapienza, P., Schnabel, J., Schumann, J., Schüssler, F., Spurio, M., Stolarczyk, Th., Taiuti, M., Tayalati, Y., Tingay, S. J., Vallage, B., Van Elewyck, V., Versari, F., Viola, S., Vivolo, D., Wilms, J., Zavatarelli, S., Zegarelli, A., Zornoza, J. D., and Zúñiga, J.
Subjects: Physics - Atmospheric and Oceanic Physics, Astrophysics - Instrumentation and Methods for Astrophysics, Quantitative Biology - Populations and Evolution
Abstract: We develop a novel technique to exploit the extensive data sets provided by underwater neutrino telescopes to gain information on bioluminescence in the deep sea. The passive nature of the telescopes gives us the unique opportunity to infer information on bioluminescent organisms without actively interfering with them. We propose a statistical method that allows us to reconstruct the light emission of individual organisms, as well as their location and movement. A mathematical model is built to describe the measurement process of underwater neutrino telescopes and the signal generation of the biological organisms. The Metric Gaussian Variational Inference algorithm is used to reconstruct the model parameters using photon counts recorded by the neutrino detectors. We apply this method to synthetic data sets and data collected by the ANTARES neutrino telescope. The telescope is located 40 km off the French coast and fixed to the sea floor at a depth of 2475 m. The runs with synthetic data reveal that we can reliably model the emitted bioluminescent flashes of the organisms. Furthermore, we find that the spatial resolution of the localization of light sources highly depends on the configuration of the telescope. Precise measurements of the efficiencies of the detectors and the attenuation length of the water are crucial to reconstruct the light emission. Finally, the application to ANTARES data reveals the first precise localizations of bioluminescent organisms using neutrino telescope data.
Published: 2021

55. Sensitivity to light sterile neutrino mixing parameters with KM3NeT/ORCA

Author: Aiello, S., Albert, A., Alshamsi, M., Garre, S. Alves, Aly, Z., Ambrosone, A., Ameli, F., Andre, M., Androulakis, G., Anghinolfi, M., Anguita, M., Anton, G., Ardid, M., Ardid, S., Aublin, J., Bagatelas, C., Baret, B., Pree, S. Basegmez du, Bendahman, M., Benfenati, F., Berbee, E., Berg, A. M. van den, Bertin, V., Biagi, S., Bissinger, M., Boettcher, M., Cabo, M. Bou, Boumaaza, J., Bouta, M., Bouwhuis, M., Bozza, C., Brânzaş, H., Bretaudeau, F., Bruijn, R., Brunner, J., Bruno, R., Buis, E., Buompane, R., Busto, J., Caiffi, B., Calvo, D., Campion, S., Capone, A., Carretero, V., Castaldi, P., Celli, S., Chabab, M., Chau, N., Chen, A., Cherubini, S., Chiarella, V., Chiarusi, T., Circella, M., Cocimano, R., Coelho, J. A. B., Coleiro, A., Mollac, M. Colomer, Coniglione, R., Coyle, P., Creusot, A., Cruz, A., Cuttone, G., Dallier, R., De Martino, B., De Palma, M., Di Palma, I., Díaz, A. F., Diego-Tortosan, D., Distefano, C., Domi, A., Donzaud, C., Dornic, D., Dorr, M., Drouhin, D., Eberl, T., Eddyamoui, A., van Eeden, T., van Eijk, D., Bojaddaini, I. El, Elsaesser, D., Enzenhofer, A., Espinosa, V., Fermani, P., Ferrara, G., Filipovic, M. D., Filippini, F., Fusco, L. A., Gal, T., Mendez, J. Garcıa, Soto, A. Garcia, Garufi, F., Gatelet, Y., Geisselbrecht, N., Gialanella, L., Giorgio, E., Gozzini, S. R., Gracia, R., Graf, K., Grella, G., Guderian, D., Guid, C., Gutierrez, M., Haefner, J., Hallmann, S., Hamdaoui, H., van Haren, H., Heijboer, A., Hekalo, A., Hennig, L., Hernandez-Rey, J. J., Hofestadt, J., Huang, F., Ibnsalih, W. Idrissi, Illuminati, G., James, C. W., de Jong, M., de Jong, P., Jung, B. J., Kadler, M., Kalaczynski, P., Kalekin, O., Katz, U. F., Chowdhury, N. R. Khan, Kistauri, G., van der Knaap, F., Kooijman, P., Kouchner, A., Kulikovskiy, V., Lahmann, R., Lamoureux, M., Lara, G., Larosa, G., Lastoria, C., Breton, R. Le, Stum, S. Le, Leonardi, O., Leone, F., Leonora, E., Lessing, N., Levi, G., Lincetto, M., Clark, M. Lindsey, Lipreau, T., Longhitano, F., Lopez-Coto, D., Lygda, A., Maderer, L., Mańczak, J., Mannheim, K., Margiotta, A., Marinelli, A., Markou, C., Martin, L., Martínez-Mora, J. A., Martini, A., Marzaioli, F., Mastroianni, S., Melis, K. W., Miele, G., Migliozzi, P., Migneco, E., Mijakowski, P., Miranda, L. S., Mollo, C. M., Moser, M., Moussa, A., Muller, R., Musumeci, M., Nauta, L., Navas, S., Nicolau, C. A., Nkosi, B., Fearraigh, B. Ó, O'Sullivan, M., Organokov, M., Orlando, A., González, J. Palacios, Papalashvili, G., Papaleo, R., Pastore, C., Păun, A. M., ălaş, G. E. Păv, Pellegrino, C., Martínez, S. Peña, Perrin-Terrin, M., Pestel, V., Piattelli, P., Pieterse, C., Pisanti, O., Poirè, C., Pontoriere, V., Popa, V., Pradier, T., Probst, I., Pühlhofer, G., Pulvirenti, S., Randazzo, N., Razzaque, S., Real, D., Reck, S., Riccobene, G., Romanov, A., Rovelli, A., Greus, F. Salesa, Samtleben, D. F. E., Losa, A. Sánchez, Sanguineti, M., Santangelo, A., Santonocito, D., Sapienza, P., Schnabel, J., Schneider, M. F., Schumann, J., Schutte, H. M., Seneca, J., Sgura, I., Shanidze, R., Sharma, A., Sinopoulou, A., Spisso, B., Spurio, M., Stavropoulos, D., Stellacci, S. M., Taiuti, M., Tatone, F., Tayalati, Y., Thakore, T., Thiersen, H., Tingay, S., Tsagkli, S., Tsourapis, V., Tzamariudaki, E., Tzanetatos, D., Van Elewyck, V., Vasileiadis, G., Versari, F., Vivolo, D., de Wasseige, G., Wilms, J., Wojaczyński, R., de Wolf, E., Yousfi, T., Zavatarelli, S., Zegarelli, A., Zito, D., Zornoza, J. D., Zúñiga, J., and Zywucka, N.
Subjects: High Energy Physics - Experiment
Abstract: KM3NeT/ORCA is a next-generation neutrino telescope optimised for atmospheric neutrino oscillations studies. In this paper, the sensitivity of ORCA to the presence of a light sterile neutrino in a 3+1 model is presented. After three years of data taking, ORCA will be able to probe the active-sterile mixing angles $\theta_{14}$, $\theta_{24}$, $\theta_{34}$ and the effective angle $\theta_{\mu e}$, over a broad range of mass squared difference $\Delta m^2_{41} \sim [10^{-5}, 10]$ $\rm{eV}^2$, allowing to test the eV-mass sterile neutrino hypothesis as the origin of short baseline anomalies, as well as probing the hypothesis of a very light sterile neutrino, not yet constrained by cosmology. ORCA will be able to explore a relevant fraction of the parameter space not yet reached by present measurements.
Published: 2021

56. MeerCRAB: MeerLICHT Classification of Real and Bogus Transients using Deep Learning

Author: Hosenie, Zafiirah, Bloemen, Steven, Groot, Paul, Lyon, Robert, Scheers, Bart, Stappers, Benjamin, Stoppa, Fiorenzo, Vreeswijk, Paul, De Wet, Simon, Wolt, Marc Klein, Körding, Elmar, McBride, Vanessa, Poole, Rudolf Le, Paterson, Kerry, Pieterse, Daniëlle L. A., and Woudt, Patrick
Subjects: Astrophysics - Instrumentation and Methods for Astrophysics, Astrophysics - Astrophysics of Galaxies, Computer Science - Artificial Intelligence, Computer Science - Computer Vision and Pattern Recognition, Computer Science - Machine Learning
Abstract: Astronomers require efficient automated detection and classification pipelines when conducting large-scale surveys of the (optical) sky for variable and transient sources. Such pipelines are fundamentally important, as they permit rapid follow-up and analysis of those detections most likely to be of scientific value. We therefore present a deep learning pipeline based on the convolutional neural network architecture called $\texttt{MeerCRAB}$. It is designed to filter out the so called 'bogus' detections from true astrophysical sources in the transient detection pipeline of the MeerLICHT telescope. Optical candidates are described using a variety of 2D images and numerical features extracted from those images. The relationship between the input images and the target classes is unclear, since the ground truth is poorly defined and often the subject of debate. This makes it difficult to determine which source of information should be used to train a classification algorithm. We therefore used two methods for labelling our data (i) thresholding and (ii) latent class model approaches. We deployed variants of $\texttt{MeerCRAB}$ that employed different network architectures trained using different combinations of input images and training set choices, based on classification labels provided by volunteers. The deepest network worked best with an accuracy of 99.5$\%$ and Matthews correlation coefficient (MCC) value of 0.989. The best model was integrated to the MeerLICHT transient vetting pipeline, enabling the accurate and efficient classification of detected transients that allows researchers to select the most promising candidates for their research goals., Comment: 15 pages, 13 figures, Accepted for publication in Experimental Astronomy and appeared in the 3rd Workshop on Machine Learning and the Physical Sciences, NeurIPS 2020
Published: 2021
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57. Effects of model incompleteness on the drift-scan calibration of radio telescopes

Author: Gehlot, Bharat K., Jacobs, Daniel C., Bowman, Judd D., Mahesh, Nivedita, Murray, Steven G., Kolopanis, Matthew, Beardsley, Adam P., Abdurashidova, Zara, Aguirre, James E., Alexander, Paul, Ali, Zaki S., Balfour, Yanga, Bernardi, Gianni, Billings, Tashalee S., Bradley, Richard F., Bull, Phil, Burba, Jacob, Carey, Steve, Carilli, Chris L., Cheng, Carina, DeBoer, David R., Dexter, Matt, Acedo, Eloy de Lera, Dillon, Joshua S., Ely, John, Ewall-Wice, Aaron, Fagnoni, Nicolas, Fritz, Randall, Furlanetto, Steven R., Gale-Sides, Kingsley, Glendenning, Brian, Gorthi, Deepthi, Greig, Bradley, Grobbelaar, Jasper, Halday, Ziyaad, Hazelton, Bryna J., Hewitt, Jacqueline N., Hickish, Jack, Julius, Austin, Kern, Nicholas S., Kerrigan, Joshua, Kittiwisit, Piyanat, Kohn, Saul A., Lanman, Adam, La Plante, Paul, Lekalake, Telalo, Lewis, David, Liu, Adrian, Ma, Yin-Zhe, MacMahon, David, Malan, Lourence, Malgas, Cresshim, Maree, Matthys, Martinot, Zachary E., Matsetela, Eunice, Mesinger, Andrei, Molewa, Mathakane, Monsalve, Raul A., Morales, Miguel F., Mosiane, Tshegofalang, Neben, Abraham R., Nikolic, Bojan, Parsons, Aaron R., Pascua, Robert, Patra, Nipanjana, Pieterse, Samantha, Pober, Jonathan C., Razavi-Ghods, Nima, Ringuette, Jon, Robnett, James, Rosie, Kathryn, Santos, Mario G., Sims, Peter, Smith, Craig, Syce, Angelo, Tegmark, Max, Thyagarajan, Nithyanandan, Williams, Peter K. G., and Zheng, Haoxuan
Subjects: Astrophysics - Cosmology and Nongalactic Astrophysics, Astrophysics - Instrumentation and Methods for Astrophysics
Abstract: Precision calibration poses challenges to experiments probing the redshifted 21-cm signal of neutral hydrogen from the Cosmic Dawn and Epoch of Reionization (z~30-6). In both interferometric and global signal experiments, systematic calibration is the leading source of error. Though many aspects of calibration have been studied, the overlap between the two types of instruments has received less attention. We investigate the sky based calibration of total power measurements with a HERA dish and an EDGES style antenna to understand the role of auto-correlations in the calibration of an interferometer and the role of sky in calibrating a total power instrument. Using simulations we study various scenarios such as time variable gain, incomplete sky calibration model, and primary beam model. We find that temporal gain drifts, sky model incompleteness, and beam inaccuracies cause biases in the receiver gain amplitude and the receiver temperature estimates. In some cases, these biases mix spectral structure between beam and sky resulting in spectrally variable gain errors. Applying the calibration method to the HERA and EDGES data, we find good agreement with calibration via the more standard methods. Although instrumental gains are consistent with beam and sky errors similar in scale to those simulated, the receiver temperatures show significant deviations from expected values. While we show that it is possible to partially mitigate biases due to model inaccuracies by incorporating a time-dependent gain model in calibration, the resulting errors on calibration products are larger and more correlated. Completely addressing these biases will require more accurate sky and primary beam models., Comment: 16 pages, 13 figures, 1 table; accepted for publication in MNRAS main journal
Published: 2021
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58. Validation of the HERA Phase I Epoch of Reionization 21 cm Power Spectrum Software Pipeline

Author: Aguirre, James E., Murray, Steven G., Pascua, Robert, Martinot, Zachary E., Burba, Jacob, Dillon, Joshua S., Jacobs, Daniel C., Kern, Nicholas S., Kittiwisit, Piyanat, Kolopanis, Matthew, Lanman, Adam, Liu, Adrian, Whitler, Lily, Abdurashidova, Zara, Alexander, Paul, Ali, Zaki S., Balfour, Yanga, Beardsley, Adam P., Bernardi, Gianni, Billings, Tashalee S., Bowman, Judd D., Bradley, Richard F., Bull, Philip, Carey, Steve, Carilli, Chris L., Cheng, Carina, DeBoer, David R., Dexter, Matt, Acedo, Eloy de Lera, Ely, John, Ewall-Wice, Aaron, Fagnoni, Nicolas, Fritz, Randall, Furlanetto, Steven R., Gale-Sides, Kingsley, Glendenning, Brian, Gorthi, Deepthi, Greig, Bradley, Grobbelaar, Jasper, Halday, Ziyaad, Hazelton, Bryna J., Hewitt, Jacqueline N., Hickish, Jack, Julius, Austin, Kerrigan, Joshua, Kohn, Saul A., La Plante, Paul, Lekalake, Telalo, Lewis, David, MacMahon, David, Malan, Lourence, Malgas, Cresshim, Maree, Matthys, Matsetela, Eunice, Mesinger, Andrei, Molewa, Mathakane, Morales, Miguel F., Mosiane, Tshegofalang, Neben, Abraham R., Nikolic, Bojan, Parsons, Aaron R., Patra, Nipanjana, Pieterse, Samantha, Pober, Jonathan C., Razavi-Ghods, Nima, Ringuette, Jon, Robnett, James, Rosie, Kathryn, Santos, Mario G., Sims, Peter, Singh, Saurabh, Smith, Craig, Syce, Angelo, Thyagarajan, Nithyanandan, Williams, Peter K. G., and Zheng, Haoxuan
Subjects: Astrophysics - Instrumentation and Methods for Astrophysics
Abstract: We describe the validation of the HERA Phase I software pipeline by a series of modular tests, building up to an end-to-end simulation. The philosophy of this approach is to validate the software and algorithms used in the Phase I upper limit analysis on wholly synthetic data satisfying the assumptions of that analysis, not addressing whether the actual data meet these assumptions. We discuss the organization of this validation approach, the specific modular tests performed, and the construction of the end-to-end simulations. We explicitly discuss the limitations in scope of the current simulation effort. With mock visibility data generated from a known analytic power spectrum and a wide range of realistic instrumental effects and foregrounds, we demonstrate that the current pipeline produces power spectrum estimates that are consistent with known analytic inputs to within thermal noise levels (at the 2 sigma level) for k > 0.2 h/Mpc for both bands and fields considered. Our input spectrum is intentionally amplified to enable a strong `detection' at k ~0.2 h/Mpc -- at the level of ~25 sigma -- with foregrounds dominating on larger scales, and thermal noise dominating at smaller scales. Our pipeline is able to detect this amplified input signal after suppressing foregrounds with a dynamic range (foreground to noise ratio) of > 10^7. Our validation test suite uncovered several sources of scale-independent signal loss throughout the pipeline, whose amplitude is well-characterized and accounted for in the final estimates. We conclude with a discussion of the steps required for the next round of data analysis., Comment: 32 pages, 20 figures. Submitted to the Astrophysical Journal
Published: 2021
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59. A Real Time Processing System for Big Data in Astronomy: Applications to HERA

Author: La Plante, Paul, Williams, Peter K. G., Kolopanis, Matthew, Dillon, Joshua S., Beardsley, Adam P., Kern, Nicholas S., Wilensky, Michael, Ali, Zaki S., Abdurashidova, Zara, Aguirre, James E., Alexander, Paul, Balfour, Yanga, Bernardi, Gianni, Billings, Tashalee S., Bowman, Judd D., Bradley, Richard F., Bull, Phil, Burba, Jacob, Carey, Steve, Carilli, Chris L., Cheng, Carina, DeBoer, David R., Dexter, Matt, Acedo, Eloy de Lera, Ely, John, Ewall-Wice, Aaron, Fagnoni, Nicolas, Fritz, Randall, Furlanetto, Steven R., Gale-Sides, Kingsley, Glendenning, Brian, Gorthi, Deepthi, Greig, Bradley, Grobbelaar, Jaspar, Halday, Ziyaad, Hazelton, Bryna J., Hewitt, Jacqueline N., Hickish, Jack, Jacobs, Daniel C., Julius, Austin, Kerrigan, Joshua, Kittiwisit, Piyanat, Kohn, Saul A., Lanman, Adam, Lekalake, Telalo, Lewis, David, Liu, Adrian, MacMahon, David, Malan, Lourence, Malgas, Cresshim, Maree, Matthys, Martinot, Zachary E., Matsetela, Eunice, Mesinger, Andrei, Molewa, Mathakane, Morales, Miguel F., Mosiane, Tshegofalang, Murray, Steven, Neben, Abraham R., Nikolic, Bojan, Parsons, Aaron R., Pascua, Robert, Patra, Nipanjana, Pieterse, Samantha, Pober, Jonathan C., Razavi-Ghods, Nima, Ringuette, Jon, Robnett, James, Rosie, Kathryn, Santos, Mario G., Sims, Peter, Smith, Craig, Syce, Angelo, Thyagarajan, Nithyanandan, and Zheng, Haoxuan
Subjects: Astrophysics - Instrumentation and Methods for Astrophysics
Abstract: As current- and next-generation astronomical instruments come online, they will generate an unprecedented deluge of data. Analyzing these data in real time presents unique conceptual and computational challenges, and their long-term storage and archiving is scientifically essential for generating reliable, reproducible results. We present here the real-time processing (RTP) system for the Hydrogen Epoch of Reionization Array (HERA), a radio interferometer endeavoring to provide the first detection of the highly redshifted 21 cm signal from Cosmic Dawn and the Epoch of Reionization by an interferometer. The RTP system consists of analysis routines run on raw data shortly after they are acquired, such as calibration and detection of radio-frequency interference (RFI) events. RTP works closely with the Librarian, the HERA data storage and transfer manager which automatically ingests data and transfers copies to other clusters for post-processing analysis. Both the RTP system and the Librarian are public and open source software, which allows for them to be modified for use in other scientific collaborations. When fully constructed, HERA is projected to generate over 50 terabytes (TB) of data each night, and the RTP system enables the successful scientific analysis of these data., Comment: 15 pages, 3 figures, published in Astronomy and Computing
Published: 2021
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60. Book Review: Cultural Chauvinism: Intercultural Communication and the Politics of Superiority by Minabere Ibelema

Author: Pieterse, Jan Nederveen
Subjects: Political Science, Journalism and Professional Writing, Communication and Media Studies, Communication & Media Studies
Published: 2022

61. Search for neutrinos from the tidal disruption events AT2019dsg and AT2019fdr with the ANTARES telescope

Author: ANTARES Collaboration, Albert, A., Alves, S., André, M., Anghinolfi, M., Anton, G., Ardid, M., Aubert, J. -J., Aublin, J., Baret, B., Basa, S., Belhorma, B., Bendahman, M., Benfenati, F., Bertin, V., Biagi, S., Bissinger, M., Boumaaza, J., Bouta, M., Bouwhuis, M. C., Brânzaş, H., Bruijn, R., Brunner, J., Busto, J., Caiffi, B., Capone, A., Caramete, L., Carr, J., Carretero, V., Celli, S., Chabab, M., Chau, T. N., Moursli, R. Cherkaoui El, Chiarusi, T., Circella, M., Coleiro, A., Colomer-Molla, M., Coniglione, R., Coyle, P., Creusot, A., Díaz, A. F., de Wasseige, G., Deschamps, A., Distefano, C., Di Palma, I., Domi, A., Donzaud, C., Dornic, D., Drouhin, D., Eberl, T., van Eeden, T., Khayati, N. El, Enzenhöfer, A., Fermani, P., Ferrara, G., Filippini, F., Fusco, L., García, R., Gatelet, Y., Gay, P., Glotin, H., Gozzini, R., Graf, K., Guidi, C., Hallmann, S., van Haren, H., Heijboer, A. J., Hello, Y., Hernández-Rey, J. J., Hößl, J., Hofestädt, J., Huang, F., Illuminati, G., James, C. W., Jisse-Jung, B., de Jong, M., de Jong, P., Jongen, M., Kadler, M., Kalekin, O., Katz, U., Khan-Chowdhury, N. R., Kouchner, A., Kreykenbohm, I., Kulikovskiy, V., Lahmann, R., Breton, R. Le, Lefèvre, D., Leonora, E., Levi, G., Lincetto, M., Lopez-Coto, D., Loucatos, S., Maderer, L., Manczak, J., Marcelin, M., Margiotta, A., Marinelli, A., Martínez-Mora, J. A., Melis, K., Migliozzi, P., Moser, M., Moussa, A., Muller, R., Nauta, L., Navas, S., Nezri, E., Fearraigh, B. Ó, Organokov, M., Păvălaş, G. E., Pellegrino, C., Perrin-Terrin, M., Piattelli, P., Pieterse, C., Poirè, C., Popa, V., Pradier, T., Randazzo, N., Reck, S., Riccobene, G., Romanov, A., Greus, F. Salesa, Samtleben, D. F. E., Sánchez-Losa, A., Sanguineti, M., Sapienza, P., Schnabel, J., Schumann, J., Schüssler, F., Spurio, M., Stolarczyk, Th., Taiuti, M., Tayalati, Y., Tingay, S. J., Vallage, B., Van Elewyck, V., Versari, F., Viola, S., Vivolo, D., Wilms, J., Zavatarelli, S., Zegarelli, A., Zornoza, J. D., and Zúñiga, J.
Subjects: Astrophysics - High Energy Astrophysical Phenomena
Abstract: On October 1, 2019, the IceCube Collaboration detected a muon track neutrino with high probability of being of astrophysical origin, IC191001A. After a few hours, the tidal disruption event (TDE) AT2019dsg, observed by the Zwicky Transient Facility (ZTF), was indicated as the most likely counterpart of the IceCube track. More recently, the follow-up campaign of the IceCube alerts by ZTF suggested a second TDE, AT2019fdr, as a promising counterpart of another IceCube muon track candidate, IC200530A, detected on May 30, 2020. These are the second and third associations between astrophysical sources and high-energy neutrinos after the compelling identification of the blazar TXS 0506+056. Here, the search for ANTARES neutrinos from the directions of AT2019dsg and AT2019fdr using a time-integrated approach is presented. As no significant evidence for space clustering is found in the ANTARES data, upper limits on the one-flavour neutrino flux and fluence are set., Comment: 10 pages, 1 figure
Published: 2021
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62. Determining the Neutrino Mass Ordering and Oscillation Parameters with KM3NeT/ORCA

Author: Aiello, S., Albert, A., Garre, S. Alves, Aly, Z., Ambrosone, A., Ameli, F., Andre, M., Androulakis, G., Anghinolfi, M., Anguita, M., Anton, G., Ardid, M., Ardid, S., Aublin, J., Bagatelas, C., Baret, B., Pree, S. Basegmez du, Bendahman, M., Benfenati, F., Berbee, E., Berg, A. M. van den, Bertin, V., Biagi, S., Bissinger, M., Boettcher, M., Cabo, M. Bou, Boumaaza, J., Bouta, M., Bouwhuis, M., Bozza, C., Brânzaş, H., Bruijn, R., Brunner, J., Bruno, R., Buis, E., Buompane, R., Busto, J., Caiffi, B., Calvo, D., Capone, A., Carretero, V., Castaldi, P., Celli, S., Chabab, M., Chau, N., Chen, A., Cherubini, S., Chiarella, V., Chiarusi, T., Circella, M., Cocimano, R., Coelho, J. A. B., Coleiro, A., Molla, M. Colomer, Coniglione, R., Coyle, P., Creusot, A., Cruz, A., Cuttone, G., Dallier, R., De Martino, B., De Palma, M., Di Marino, M., Di Palma, I., Díaz, A. F., Diego-Tortosa, D., Distefano, C., Domi, A., Donzaud, C., Dornic, D., Dörr, M., Drouhin, D., Eberl, T., Eddyamoui, A., van Eeden, T., van Eijk, D., Bojaddaini, I. El, Elsaesser, D., Enzenhöfer, A., Espinosa, V., Fermani, P., Ferrara, G., Filipovic, M. D., Filippini, F., Fusco, L. A., Gal, T., Soto, A. Garcia, Garufi, F., Gatelet, Y., Geisselbrecht, N., Gialanella, L., Giorgio, E., Gozzini, S. R., Gracia, R., Graf, K., Grasso, D., Grella, G., Guderian, D., Guidi, C., Haefner, J., Hallmann, S., Hamdaoui, H., van Haren, H., Heijboer, A., Hekalo, A., Hennig, L., Hernández-Rey, J. J., Hofestädt, J., Huang, F., Ibnsalih, W. Idrissi, Illuminati, G., James, C. W., de Jong, M., de Jong, P., Jung, B. J., Kadler, M., Kalaczyński, P., Kalekin, O., Katz, U. F., Chowdhury, N. R. Khan, Kistauri, G., van der Knaap, F., Kooijman, P., Kouchner, A., Kreter, M., Kulikovskiy, V., Lahmann, R., Lamoureux, M., Larosa, G., Lastoria, C., Breton, R. Le, Stum, S. Le, Leonardi, O., Leone, F., Leonora, E., Lessing, N., Levi, G., Lincetto, M., Clark, M. Lindsey, Lipreau, T., Longhitano, F., Lopez-Coto, D., Maderer, L., Mańczak, J., Mannheim, K., Margiotta, A., Marinelli, A., Markou, C., Martin, L., Martínez-Mora, J. A., Martini, A., Marzaioli, F., Mastroianni, S., Melis, K. W., Miele, G., Migliozzi, P., Migneco, E., Mijakowski, P., Miranda, L. S., Mollo, C. M., Morganti, M., Moser, M., Moussa, A., Muller, R., Musumeci, M., Nauta, L., Navas, S., Nicolau, C. A., Fearraigh, B. Ó, O'Sullivan, M., Organokov, M., Orlando, A., González, J. Palacios, Papalashvili, G., Papaleo, R., Pastore, C., Păun, A. M., Păvălaş, G. E., Pellegrino, C., Perrin-Terrin, M., Pestel, V., Piattelli, P., Pieterse, C., Pikounis, K., Pisanti, O., Poirè, C., Popa, V., Pradier, T., Pühlhofer, G., Pulvirenti, S., Rabyang, O., Raffaelli, F., Randazzo, N., Razzaque, S., Real, D., Reck, S., Riccobene, G., Romanov, A., Rovelli, A., Greus, F. Salesa, Samtleben, D. F. E., Losa, A. Sánchez, Sanguineti, M., Santangelo, A., Santonocito, D., Sapienza, P., Schnabel, J., Schneider, M. F., Schumann, J., Schutte, H. M., Seneca, J., Sgura, I., Shanidze, R., Sharma, A., Sinopoulou, A., Spisso, B., Spurio, M., Stavropoulos, D., Stellacci, S. M., Taiuti, M., Tayalati, Y., Tenllado, E., Thiersen, H., Tingay, S., Tsourapis, V., Tzamariudaki, E., Tzanetatos, D., Van Elewyck, V., Vasileiadis, G., Versari, F., Vivolo, D., de Wasseige, G., Wilms, J., Wojaczyński, R., de Wolf, E., Yousfi, T., Zavatarelli, S., Zegarelli, A., Zito, D., Zornoza, J. D., Zúñiga, J., and Zywucka, N.
Subjects: High Energy Physics - Experiment
Abstract: The next generation of water Cherenkov neutrino telescopes in the Mediterranean Sea are under construction offshore France (KM3NeT/ORCA) and Sicily (KM3NeT/ARCA). The KM3NeT/ORCA detector features an energy detection threshold which allows to collect atmospheric neutrinos to study flavour oscillation. This paper reports the KM3NeT/ORCA sensitivity to this phenomenon. The event reconstruction, selection and classification are described. The sensitivity to determine the neutrino mass ordering was evaluated and found to be 4.4 $\sigma$ if the true ordering is normal and 2.3 $\sigma$ if inverted, after three years of data taking. The precision to measure $\Delta m^2_{32}$ and $\theta_{23}$ were also estimated and found to be $85\cdot10^{-6}$ eV$^2$ and $(^{+1.9}_{-3.1})^{\circ}$ for normal neutrino mass ordering and, $75\cdot10^{-6}$ eV$^2$ and $(^{+2.0}_{-7.0})^{\circ}$ for inverted ordering. Finally, a unitarity test of the leptonic mixing matrix by measuring the rate of tau neutrinos is described. Three years of data taking were found to be sufficient to exclude $\nu_{\tau}$ and $\bar{\nu}_{\tau}$ event rate variations larger than 20% at $3\sigma$ level., Comment: Accepted for publication at EPJ-C
Published: 2021
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63. Methods of Error Estimation for Delay Power Spectra in $21\,\textrm{cm}$ Cosmology

Author: Tan, Jianrong, Liu, Adrian, Kern, Nicholas S., Abdurashidova, Zara, Aguirre, James E., Alexander, Paul, Ali, Zaki S., Balfour, Yanga, Beardsley, Adam P., Bernardi, Gianni, Billings, Tashalee S., Bowman, Judd D., Bradley, Richard F., Bull, Philip, Burba, Jacob, Carey, Steven, Carilli, Christopher L., Cheng, Carina, DeBoer, David R., Dexter, Matt, Acedo, Eloy de Lera, Dillon, Joshua S., Ely, John, Ewall-Wice, Aaron, Fagnoni, Nicolas, Fritz, Randall, Furlanetto, Steve R., Gale-Sides, Kingsley, Glendenning, Brian, Gorthi, Deepthi, Greig, Bradley, Grobbelaar, Jasper, Halday, Ziyaad, Hazelton, Bryna J., Hewitt, Jacqueline N., Hickish, Jack, Jacobs, Daniel C., Julius, Austin, Kerrigan, Joshua, Kittiwisit, Piyanat, Kohn, Saul A., Kolopanis, Matthew, Lanman, Adam, La Plante, Paul, Lekalake, Telalo, MacMahon, David, Malan, Lourence, Malgas, Cresshim, Maree, Matthys, Martinot, Zachary E., Matsetela, Eunice, Mesinger, Andrei, Molewa, Mathakane, Morales, Miguel F., Mosiane, Tshegofalang, Murray, Steven G., Neben, Abraham R., Nikolic, Bojan, Nunhokee, Chuneeta D., Parsons, Aaron R., Patra, Nipanjana, Pieterse, Samantha, Pober, Jonathan C., Razavi-Ghods, Nima, Ringuette, Jon, Robnett, James, Rosie, Kathryn, Sims, Peter, Singh, Saurabh, Smith, Craig, Syce, Angelo, Thyagarajan, Nithyanandan, Williams, Peter K. G., and Zheng, Haoxuan
Subjects: Astrophysics - Instrumentation and Methods for Astrophysics, Astrophysics - Cosmology and Nongalactic Astrophysics
Abstract: Precise measurements of the 21 cm power spectrum are crucial for understanding the physical processes of hydrogen reionization. Currently, this probe is being pursued by low-frequency radio interferometer arrays. As these experiments come closer to making a first detection of the signal, error estimation will play an increasingly important role in setting robust measurements. Using the delay power spectrum approach, we have produced a critical examination of different ways that one can estimate error bars on the power spectrum. We do this through a synthesis of analytic work, simulations of toy models, and tests on small amounts of real data. We find that, although computed independently, the different error bar methodologies are in good agreement with each other in the noise-dominated regime of the power spectrum. For our preferred methodology, the predicted probability distribution function is consistent with the empirical noise power distributions from both simulated and real data. This diagnosis is mainly in support of the forthcoming HERA upper limit, and also is expected to be more generally applicable., Comment: 35 Pages, 9 Figures, 4 Tables. Replaced with accepted ApJ version; some clarifying text added in response to referee comments with no changes to results
Published: 2021
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64. Multi-frequency observations of SGR J1935+2154

Author: Bailes, M., Bassa, C. G., Bernardi, G., Buchner, S., Burgay, M., Caleb, M., Cooper, A. J., Desvignes, G., Groot, P. J., Heywood, I., Jankowski, F., Karuppusamy, R., Kramer, M., Malenta, M., Naldi, G., Pilia, M., Pupillo, G., Rajwade, K. M., Spitler, L., Surnis, M., Stappers, B. W., Addis, A., Bloemen, S., Bezuidenhout, M. C., Bianchi, G., Champion, D. J., Chen, W., Driessen, L. N., Geyer, M., Gourdji, K., Hessels, J. W. T., Kondratiev, V. I., Klein-Wolt, M., K"ording, E., Poole, R. Le, Liu, K., Lower, M. E., Lyne, A. G., Magro, A., McBride, V., Mickaliger, M. B., Morello, V., Parthasarathy, A., Paterson, K., Perera, B. B. P., Pieterse, D. L. A., Pleunis, Z., Possenti, A., Rowlinson, A., Serylak, M., Setti, G., Tavani, M., Wijers, R. A. M. J., ter Veen, S., Krishnan, V. Venkatraman, Vreeswijk, P., and Woudt, P. A.
Subjects: Astrophysics - High Energy Astrophysical Phenomena
Abstract: Magnetars are a promising candidate for the origin of Fast Radio Bursts (FRBs). The detection of an extremely luminous radio burst from the Galactic magnetar SGR J1935+2154 on 2020 April 28 added credence to this hypothesis. We report on simultaneous and non-simultaneous observing campaigns using the Arecibo, Effelsberg, LOFAR, MeerKAT, MK2 and Northern Cross radio telescopes and the MeerLICHT optical telescope in the days and months after the April 28 event. We did not detect any significant single radio pulses down to fluence limits between 25 mJy ms and 18 Jy ms. Some observing epochs overlapped with times when X-ray bursts were detected. Radio images made on four days using the MeerKAT telescope revealed no point-like persistent or transient emission at the location of the magnetar. No transient or persistent optical emission was detected over seven days. Using the multi-colour MeerLICHT images combined with relations between DM, NH and reddening we constrain the distance to SGR J1935+2154, to be between 1.5 and 6.5 kpc. The upper limit is consistent with some other distance indicators and suggests that the April 28 burst is closer to two orders of magnitude less energetic than the least energetic FRBs. The lack of single-pulse radio detections shows that the single pulses detected over a range of fluences are either rare, or highly clustered, or both. It may also indicate that the magnetar lies somewhere between being radio-quiet and radio-loud in terms of its ability to produce radio emission efficiently., Comment: Accepted for publication in MNRAS. Corresponding author B. W. Stappers
Published: 2021
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65. GW190814 follow-up with the optical telescope MeerLICHT

Author: de Wet, S., Groot, P. J., Bloemen, S., Poole, R. Le, Klein-Wolt, M., Körding, E., McBride, V., Paterson, K., Pieterse, D. L. A., Vreeswijk, P. M., and Woudt, P.
Subjects: Astrophysics - High Energy Astrophysical Phenomena
Abstract: The Advanced LIGO and Virgo gravitational wave observatories detected a signal on 2019 August 14 during their third observing run, named GW190814. A large number of electromagnetic facilities conducted follow-up campaigns in the search for a possible counterpart to the gravitational wave event, which was made especially promising given the early source classification of a neutron star-black hole merger.We present the results of the GW follow-up campaign taken with the wide-field optical telescope MeerLICHT, located at the South African Astronomical Observatory Sutherland site. We use our results to constrain possible kilonova models. MeerLICHT observed more than 95% of the probability localisation each night for over a week in three optical bands (u,q,i) with our initial observations beginning almost 2 hours after the GW detection. We describe the search for new transients in MeerLICHT data and investigate how our limiting magnitudes can be used to constrain an AT2017gfo-like kilonova. A single new transient was found in our analysis of MeerLICHT data, which we exclude from being the electromagnetic counterpart to GW190814 due to the existence of a spatially unresolved source at the transient's coordinates in archival data. Using our limiting magnitudes, the confidence with which we can exclude the presence of an AT2017gfo-like kilonova at the distance of GW190814 was low ($<10^{-4}$)., Comment: 19 pages, 6 figures, accepted by A&A
Published: 2021
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66. Connectivity and Global Studies

Author: Pieterse, Jan Nederveen
Subjects: Social Science
Abstract: The book explores intricacies of connectivity through genetic codes, technology, art, borders, populism and much more. This is a major contribution to understanding globalization.
Published: 2021

67. The KM3NeT potential for the next core-collapse supernova observation with neutrinos

Author: KM3NeT Collaboration, Aiello, S., Albert, A., Garre, S. Alves, Aly, Z., Ambrosone, A., Ameli, F., Andre, M., Androulakis, G., Anghinolfi, M., Anguita, M., Anton, G., Ardid, M., Ardid, S., Aublin, J., Bagatelas, C., Baret, B., Pree, S. Basegmez du, Bendahman, M., Benfenati, F., Berbee, E., Berg, A. M. van den, Bertin, V., Biagi, S., Bissinger, M., Boettcher, M., Cabo, M. Bou, Boumaaza, J., Bouta, M., Bouwhuis, M., Bozza, C., Brânzaş, H., Bruijn, R., Brunner, J., Buis, E., Buompane, R., Busto, J., Caiffi, B., Calvo, D., Capone, A., Carretero, V., Castaldi, P., Celli, S., Chabab, M., Chau, N., Chen, A., Cherubini, S., Chiarella, V., Chiarusi, T., Circella, M., Cocimano, R., Coelho, J. A. B., Coleiro, A., Molla, M. Colomer, Coniglione, R., Coyle, P., Creusot, A., Cuttone, G., Dallier, R., De Martino, B., De Palma, M., Di Marino, M., Di Palma, I., Dıaz, A. F., Diego-Tortosa, D., Distefano, C., Domi, A., Donzaud, C., Dornic, D., Dörr, M., Drouhin, D., Eberl, T., Eddyamoui, A., van Eeden, T., van Eijk, D., Bojaddaini, I. El, Elsaesser, D., Enzenhöfer, A., Espinosa, V., Fermani, P., Ferrara, G., Filipović, M. D., Filippini, F., Fusco, L. A., Gabella, O., Gal, T., Soto, A. Garcia, Garufi, F., Gatelet, Y., Geißelbrecht, N., Gialanella, L., Giorgio, E., Gozzini, S. R., Gracia, R., Graf, K., Grasso, D., Grella, G., Guderian, D., Guidi, C., Haefner, J., Hamdaoui, H., van Haren, H., Heijboer, A., Hekalo, A., Hennig, L., Hernández-Rey, J. J., Hofestädt, J., Huang, F., Ibnsalih, W. Idrissi, Illuminati, G., James, C. W., de Jong, M., de Jong, P., Jung, B. J., Kadler, M., Kalaczyński, P., Kalekin, O., Katz, U. F., Chowdhury, N. R. Khan, Kistauri, G., van der Knaap, F., Kooijman, P., Kouchner, A., Kreter, M., Kulikovskiy, V., Lahmann, R., Lamoureux, M., Larosa, G., Breton, R. Le, Stum, S. Le, Leonardi, O., Leone, F., Leonora, E., Lessing, N., Levi, G., Lincetto, M., Clark, M. Lindsey, Lipreau, T., Longhitano, F., Lopez-Coto, D., Maderer, L., Mańczak, J., Mannheim, K., Margiotta, A., Marinelli, A., Markou, C., Martin, L., Martınez-Mora, J. A., Martini, A., Marzaioli, F., Mastroianni, S., Mazzou, S., Melis, K. W., Miele, G., Migliozzi, P., Migneco, E., Mijakowski, P., Miranda, L. S., Mollo, C. M., Morganti, M., Moser, M., Moussa, A., Muller, R., Musumeci, M., Nauta, L., Navas, S., Nicolau, C. A., Fearraigh, B. Ó, O'Sullivan, M., Organokov, M., Orlando, A., González, J. Palacios, Papalashvili, G., Papaleo, R., Passaro, G., Pastore, C., Păun, A. M., Păvălaş, G. E., Pellegrino, C., Perrin-Terrin, M., Pestel, V., Piattelli, P., Pieterse, C., Pikounis, K., Pisanti, O., Poirè, C., Popa, V., Pradier, T., Pühlhofer, G., Pulvirenti, S., Rabyang, O., Raffaelli, F., Randazzo, N., Razzaque, S., Real, D., Reck, S., Riccobene, G., Rivoire, S., Romanov, A., Rovelli, A., Greus, F. Salesa, Samtleben, D. F. E., Losa, A. Sánchez, Sanguineti, M., Santangelo, A., Santonocito, D., Sapienza, P., Schnabel, J., Schneider, M. F., Schumann, J., Schutte, H. M., Seneca, J., Sgura, I., Shanidze, R., Sharma, A., Simeone, F., Sinopoulou, A., Spisso, B., Spurio, M., Stavropoulos, D., Stellacci, S. M., Taiuti, M., Tayalati, Y., Tenllado, E., Thakore, T., Thiersen, H., Tingay, S., Tsourapis, V., Tzamariudaki, E., Tzanetatos, D., Unbehaun, T., Van Elewyck, V., Vannoye, G., Vasileiadis, G., Vermariën, G., Versari, F., Viola, S., Vivolo, D., de Wasseige, G., Wilms, J., Wojaczyński, R., de Wolf, E., Zavatarelli, S., Zegarelli, A., Zito, D., Zornoza, J. D., Zúñiga, J., and Zywucka, N.
Subjects: Astrophysics - High Energy Astrophysical Phenomena
Abstract: The KM3NeT research infrastructure is under construction in the Mediterranean Sea. It consists of two water Cherenkov neutrino detectors, ARCA and ORCA, aimed at neutrino astrophysics and oscillation research, respectively. Instrumenting a large volume of sea water with $\sim$ 6,200 optical modules comprising a total of $\sim$ 200,000 photomultiplier tubes, KM3NeT will achieve sensitivity to $\sim$ 10 MeV neutrinos from Galactic and near-Galactic core-collapse supernovae through the observation of coincident hits in photomultipliers above the background. In this paper, the sensitivity of KM3NeT to a supernova explosion is estimated from detailed analyses of background data from the first KM3NeT detection units and simulations of the neutrino signal. The KM3NeT observational horizon (for a $5\,\sigma$ discovery) covers essentially the Milky-Way and for the most optimistic model, extends to the Small Magellanic Cloud ($\sim$ 60 kpc). Detailed studies of the time profile of the neutrino signal allow assessment of the KM3NeT capability to determine the arrival time of the neutrino burst with a few milliseconds precision for sources up to 5$-$8 kpc away, and detecting the peculiar signature of the standing accretion shock instability if the core-collapse supernova explosion happens closer than 3$-$5 kpc, depending on the progenitor mass. KM3NeT's capability to measure the neutrino flux spectral parameters is also presented., Comment: submitted to EPJC
Published: 2021
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68. Measurement of the atmospheric $\nu_e$ and $\nu_\mu$ energy spectra with the ANTARES neutrino telescope

Author: Albert, A., Alves, S., André, M., Anghinolfi, M., Anton, G., Ardid, M., Aubert, J. -J., Aublin, J., Baret, B., Basa, S., Belhorma, B., Bendahman, M., Bertin, V., Biagi, S., Bissinger, M., Boumaaza, J., Bouta, M., Bouwhuis, M. C., Brânzaş, H., Bruijn, R., Brunner, J., Busto, J., Capone, A., Caramete, L., Carr, J., Carretero, V., Celli, S., Chabab, M., Chau, T. N., Moursli, R. Cherkaoui El, Chiarusi, T., Circella, M., Coleiro, A., Colomer-Molla, M., Coniglione, R., Coyle, P., Creusot, A., Díaz, A. F., de Wasseige, G., Deschamps, A., Distefano, C., Di Palma, I., Domi, A., Donzaud, C., Dornic, D., Drouhin, D., Eberl, T., Khayati, N. El, Enzenhöfer, A., Fermani, P., Ferrara, G., Filippini, F., Fusco, L., García, R., Gatelet, Y., Gay, P., Glotin, H., Gozzini, R., Graf, K., Guidi, C., Hallmann, S., van Haren, H., Heijboer, A. J., Hello, Y., Hernández-Rey, J. J., Hößl, J., Hofestädt, J., Huang, F., Illuminati, G., James, C. W., Jisse-Jung, B., de Jong, M., de Jong, P., Jongen, M., Kadler, M., Kalekin, O., Katz, U., Khan-Chowdhury, N. R., Kouchner, A., Kreykenbohm, I., Kulikovskiy, V., Lahmann, R., Breton, R. Le, Lefèvre, D., Leonora, E., Levi, G., Lincetto, M., Lopez-Coto, D., Loucatos, S., Maderer, L., Manczak, J., Marcelin, M., Margiotta, A., Marinelli, A., Martínez-Mora, J. A., Melis, K., Migliozzi, P., Moser, M., Moussa, A., Muller, R., Nauta, L., Navas, S., Nezri, E., Nunez-Castineyra, A., O'Fearraigh, B., Organokov, M., Pă, G. E., vă, laş, Pellegrino, C., Perrin-Terrin, M., Piattelli, P., Pieterse, C., Poirè, C., Popa, V., Pradier, T., Randazzo, N., Reck, S., Riccobene, G., Greus, F. Salesa, Samtleben, D. F. E., Sánchez-Losa, A., Sanguineti, M., Sapienza, P., Schnabel, J., Schumann, J., Schüssler, F., Spurio, M., Stolarczyk, Th., Taiuti, M., Tayalati, Y., Thakore, T., Tingay, S. J., Vallage, B., Van Elewyck, V., Versari, F., Viola, S., Vivolo, D., Wilms, J., Zegarelli, A., Zornoza, J. D., and Zúniga, J.
Subjects: High Energy Physics - Experiment, Astrophysics - High Energy Astrophysical Phenomena
Abstract: This letter presents a combined measurement of the energy spectra of atmospheric $\nu_e$ and $\nu_\mu$ in the energy range between $\sim$100 GeV and $\sim$50 TeV with the ANTARES neutrino telescope. The analysis uses 3012 days of detector livetime in the period 2007--2017, and selects 1016 neutrinos interacting in (or close to) the instrumented volume of the detector, yielding shower-like events (mainly from $\nu_e+\overline \nu_e$ charged current plus all neutrino neutral current interactions) and starting track events (mainly from $\nu_\mu + \overline \nu_\mu$ charged current interactions). The contamination by atmospheric muons in the final sample is suppressed at the level of a few per mill by different steps in the selection analysis, including a Boosted Decision Tree classifier. The distribution of reconstructed events is unfolded in terms of electron and muon neutrino fluxes. The derived energy spectra are compared with previous measurements that, above 100 GeV, are limited to experiments in polar ice and, for $\nu_\mu$, to Super-Kamiokande., Comment: Accepted to PLB
Published: 2021
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69. Mechanical and Optical Design of the HIRAX Radio Telescope

Author: Saliwanchik, Benjamin R. B., Ewall-Wice, Aaron, Crichton, Devin, Kuhn, Emily R., Ölçek, Deniz, Bandura, Kevin, Bucher, Martin, Chang, Tzu-Ching, Chiang, H. Cynthia, Gerodias, Kit, Kesebonye, Kabelo, MacKay, Vincent, Moodley, Kavilan, Newburgh, Laura B., Nistane, Viraj, Peterson, Jeffrey B., Pieters, Elizabeth, Pieterse, Carla, Vanderlinde, Keith, Sievers, Jonathan L., Weltman, Amanda, and Wulf, Dallas
Subjects: Astrophysics - Instrumentation and Methods for Astrophysics
Abstract: The Hydrogen Intensity and Real-time Analysis eXperiment (HIRAX) is a planned interferometric radio telescope array that will ultimately consist of 1024 close packed 6 m dishes that will be deployed at the SKA South Africa site. HIRAX will survey the majority of the southern sky to measure baryon acoustic oscillations (BAO) using the 21 cm hyperfine transition of neutral hydrogen. It will operate between 400-800 MHz with 391 kHz resolution, corresponding to a redshift range of $0.8 < z < 2.5$ and a minimum $\Delta z/z$ of ~0.003. One of the primary science goals of HIRAX is to constrain the dark energy equation of state by measuring the BAO scale as a function of redshift over a cosmologically significant range. Achieving this goal places stringent requirements on the mechanical and optical design of the HIRAX instrument which are described in this paper. This includes the simulations used to optimize the instrument, including the dish focal ratio, receiver support mechanism, and instrument cabling. As a result of these simulations, the dish focal ratio has been reduced to 0.23 to reduce inter-dish crosstalk, the feed support mechanism has been redesigned as a wide (35 cm diam.) central column, and the feed design has been modified to allow the cabling for the receiver to pass directly along the symmetry axis of the feed and dish in order to eliminate beam asymmetries and reduce sidelobe amplitudes. The beams from these full-instrument simulations are also used in an astrophysical m-mode analysis pipeline which is used to evaluate cosmological constraints and determine potential systematic contamination due to physical non-redundancies of the array elements. This end-to-end simulation pipeline was used to inform the dish manufacturing and assembly specifications which will guide the production and construction of the first-stage HIRAX 256-element array., Comment: 20 pages, 11 figures
Published: 2021

70. Plant commensal type VII secretion system causes iron leakage from roots to promote colonization

Author: Liu, Yunpeng, Shu, Xia, Chen, Lin, Zhang, Huihui, Feng, Haichao, Sun, Xiting, Xiong, Qin, Li, Guangqi, Xun, Weibing, Xu, Zhihui, Zhang, Nan, Pieterse, Corné M. J., Shen, Qirong, and Zhang, Ruifu
Published: 2023
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71. Rule of Law Through the ‘Urban Turn’ in South African Constitutionalism

Author: Pieterse, Marius
Published: 2023
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72. Patients’ perspectives towards biologic dose reduction in psoriasis: a qualitative study

Author: van der Schoot, L. S., Verhoef, L. M., van Ee, I., van Oort, F. P. A. H., Pieterse, A. H., Seyger, M. M. B., de Jong, E. M. G. J., and van den Reek, J. M. P. A.
Published: 2023
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73. ANTARES search for point-sources of neutrinos using astrophysical catalogs: a likelihood stacking analysis

Author: Albert, A., André, M., Anghinolfi, M., Anton, G., Ardid, M., Aubert, J. -J., Aublin, J., Baret, B., Basa, S., Belhorma, B., Bertin, V., Biagi, S., Bissinger, M., Boumaaza, J., Bouta, M., Bouwhuis, M. C., Branzas, H., Bruijn, R., Brunner, J., Busto, J., Capone, A., Caramete, L., Carr, J., Carretero, V., Celli, S., Chabab, M., Chau, T. N., Moursli, R., Chiarusi, T., Circella, M., Coleiro, A., Colomer-Molla, M., Coniglione, R., Coyle, P., Creusot, A., Diaz, A. F., de Wasseige, G., Deschamps, A., Distefano, C., di Palma, I., Domi, A., Donzaud, C., Dornic, D., Drouhin, D., Eberl, T., Khayati, N., Enzenhofer, A., Fermani, P., Ferrara, G., Filippini, F., Fusco, L., Gatelet, Y., Gay, P., Glotin, H., Gozzini, R., Gracia, R., Graf, K., Guidi, C., Hallmann, S., Haren, H., Heijboer, A. J., Hello, Y., Hernandez-Rey, J. J., Hössl, J., Hofestädt, J., Huang, F., Illuminati, G., James, C. W., Jisse-Jung, B., Jong, M., Jong, P., Jongen, M., Kadler, M., Kalekin, O., Katz, U., Khan-Chowdhury, N. R., Kouchner, A., Kreykenbohm, I., Kulikovskiy, V., Lahmann, R., Breton, R., Lefèvre, D., Leonora, E., Levi, G., Lincetto, M., Lopez-Coto, D., Loucatos, S., Maderer, L., Manczak, J., Marcelin, M., Margiotta, A., Marinelli, A., Martinez-Mora, J. A., Mazzou, S., Melis, K., Migliozzi, P., Moser, M., Moussa, A., Muller, R., Nauta, L., Navas, S., Nezri, E., Nunez-Castineyra, A., O'Fearraigh, B., Organokov, M., Palavas, G. E., Pellegrino, C., Perrin-Terrin, M., Piattelli, P., Pieterse, C., Poirè, C., Popa, V., Pradier, T., Randazzo, N., Reck, S., Riccobene, G., Greus, F., Samtleben, D. F., Sanchez-Losa, A., Sanguineti, M., Sapienza, P., Schnabel, J., Schussler, F., Spurio, M., Stolarczyk, Th., Taiuti, M., Tayalati, Y., Thakore, T., Tingay, S. J., Vallage, B., Elewyck, V., Versari, F., Viola, S., Vivolo, D., Wilms, J., Zegarelli, A., Zornoza, J. D., Zuniga, J., and Buson, S.
Subjects: Astrophysics - High Energy Astrophysical Phenomena
Abstract: A search for astrophysical point-like neutrino sources using the data collected by the ANTARES detector between January 29, 2007 and December 31, 2017 is presented. A likelihood stacking method is used to assess the significance of an excess of muon neutrinos inducing track-like events in correlation with the location of a list of possible sources. Different sets of objects are tested in the analysis: a) a sub-sample of the \textit{Fermi} 3LAC catalog of blazars, b) a jet-obscured AGN population, c) a sample of soft gamma-ray selected radio galaxies, d) a star-forming galaxy catalog , and e) a public sample of 56 very-high-energy track events from the IceCube experiment. None of the tested sources shows a significant association with the sample of neutrinos detected by ANTARES. The smallest p-value is obtained for the radio galaxies catalog with an equal weights hypothesis, with a pre-trial p-value equivalent to a $2.8 \, \sigma$ excess, equivalent to $1.6 \, \sigma$ post-trial. In addition, the results of a dedicated analysis for the blazar MG3 J225517+2409 are also reported: this source is found to be the most significant within the \textit{Fermi} 3LAC sample, with 5 ANTARES events located at less than one degree from the source. This blazar showed evidence of flaring activity in \textit{Fermi} data, in space-time coincidence with a high-energy track detected by IceCube. An \emph{a posteriori} significance of $2.0\, \sigma$ for the combination of ANTARES and IceCube data is reported.
Published: 2020
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74. Anomalous gas in ESO 149-G003: A MeerKAT-16 View

Author: Józsa, Gyula I. G., Thorat, Kshitij, Kamphuis, Peter, Sebokolodi, Lerato, Maina, Eric K., Wang, Jing, Pieterse, Daniëlle L. A., Groot, Paul, Ramaila, Athanaseus J. T., Serra, Paolo, Andati, Lexy A. L., de Blok, W. J. G., Hugo, Benjamin V., Kleiner, Dane, Maccagni, Filippo M., Makhathini, Sphesihle, Molnár, Dániel Cs., Ramatsoku, Mpati, Smirnov, Oleg M., Bloemen, Steven, Paterson, Kerry, Vreeswijk, Paul, McBride, Vanessa, Klein-Wolt, Marc, Woudt, Patrick, Körding, Elmar, Poole, Rudolf Le, Goedhart, Sharmila, Passmoor, Sean S., Serylak, Maciej, and Dettmar, Ralf-Jürgen
Subjects: Astrophysics - Astrophysics of Galaxies
Abstract: ESO 149-G003 is a close-by, isolated dwarf irregular galaxy. Previous observations with the ATCA indicated the presence of anomalous neutral hydrogen (HI) deviating from the kinematics of a regularly rotating disc. We conducted follow-up observations with the MeerKAT radio telescope during the 16-dish Early Science programme as well as with the MeerLICHT optical telescope. Our more sensitive radio observations confirm the presence of anomalous gas in ESO 149-G003, and further confirm the formerly tentative detection of an extraplanar HI component in the galaxy. Employing a simple tilted-ring model, in which the kinematics is determined with only four parameters but including morphological asymmetries, we reproduce the galaxy's morphology, which shows a high degree of asymmetry. By comparing our model with the observed HI, we find that in our model we cannot account for a significant (but not dominant) fraction of the gas. From the differences between our model and the observed data cube we estimate that at least 7%-8% of the HI in the galaxy exhibits anomalous kinematics, while we estimate a minimum mass fraction of less than 1% for the morphologically confirmed extraplanar component. We investigate a number of global scaling relations and find that, besides being gas-dominated with a neutral gas-to-stellar mass ratio of 1.7, the galaxy does not show any obvious global peculiarities. Given its isolation, as confirmed by optical observations, we conclude that the galaxy is likely currently acquiring neutral gas. It is either re-accreting gas expelled from the galaxy or accreting pristine intergalactic material., Comment: 16 pages, 14 figures, MNRAS, Accepted 2020 December 2, in original form 2019 September 18
Published: 2020
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75. ANTARES upper limits on the multi-TeV neutrino emission from the GRBs detected by IACTs

Author: ANTARES Collaboration, Albert, A., André, M., Anghinolfi, M., Anton, G., Ardid, M., Aubert, J. -J., Aublin, J., Baret, B., Basa, S., Belhorma, B., Bertin, V., Biagi, S., Bissinger, M., Boumaaza, J., Bouta, M., Bouwhuis, M. C., Brânzaş, H., Bruijn, R., Brunner, J., Busto, J., Capone, A., Caramete, L., Carr, J., Carretero, V., Celli, S., Chabab, M., Chau, T. N., Moursli, R. Cherkaoui El, Chiarusi, T., Circella, M., Coleiro, A., Colomer-Molla, M., Coniglione, R., Coyle, P., Creusot, A., Díaz, A. F., de Wasseige, G., Deschamps, A., Distefano, C., Di Palma, I., Domi, A., Donzaud, C., Dornic, D., Drouhin, D., Eberl, T., Khayati, N. El, Enzenhöfer, A., Ettahiri, A., Fermani, P., Ferrara, G., Filippini, F., Fusco, L., García, R., Gay, P., Glotin, H., Gozzini, R., Graf, K., Guidi, C., Hallmann, S., van Haren, H., Heijboer, A. J., Hello, Y., Hernández-Rey, J. J., Hößl, J., Hofestädt, J., Huang, F., Illuminati, G., James, C. W., Jisse-Jung, B., de Jong, M., de Jong, P., Jongen, M., Kadler, M., Kalekin, O., Katz, U., Khan-Chowdhury, N. R., Kouchner, A., Kreykenbohm, I., Kulikovskiy, V., Lahmann, R., Breton, R. Le, Lefèvre, D., Leonora, E., Levi, G., Lincetto, M., Lopez-Coto, D., Loucatos, S., Maderer, L., Manczak, J., Marcelin, M., Margiotta, A., Marinelli, A., Martínez-Mora, J. A., Mazzou, S., Melis, K., Migliozzi, P., Moser, M., Moussa, A., Muller, R., Nauta, L., Navas, S., Nezri, E., Nuñez-Castiñeyra, A., O'Fearraigh, B., Organokov, M., Păvălaş, G. E., Pellegrino, C., Perrin-Terrin, M., Piattelli, P., Pieterse, C., Poirè, C., Popa, V., Pradier, T., Randazzo, N., Reck, S., Riccobene, G., Sánchez-Losa, A., Samtleben, D. F. E., Sanguineti, M., Sapienza, P., Schnabel, J., Schüssler, F., Spurio, M., Stolarczyk, Th., Taiuti, M., Tayalati, Y., Thakore, T., Tingay, S. J., Vallage, B., Van Elewyck, V., Versari, F., Viola, S., Vivolo, D., Wilms, J., Zegarelli, A., Zornoza, J. D., and Zúñiga, J.
Subjects: Astrophysics - High Energy Astrophysical Phenomena
Abstract: The first gamma-ray burst detections by Imaging Atmospheric Cherenkov Telescopes have been recently announced: GRB 190114C, detected by MAGIC, GRB 180720B and GRB 190829A, observed by H.E.S.S. A dedicated search for neutrinos in space and time coincidence with the gamma-ray emission observed by IACTs has been performed using ANTARES data. The search covers both the prompt and afterglow phases, yielding no neutrinos in coincidence with the three GRBs studied. Upper limits on the energetics of the neutrino emission are inferred. The resulting upper limits are several orders of magnitude above the observed gamma-ray emission, and they do not allow to constrain the available models., Comment: accepted for publication in JCAP
Published: 2020
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76. MeerKAT HI commissioning observations of MHONGOOSE galaxy ESO 302-G014

Author: de Blok, W. J. G., Athanassoula, E., Bosma, A., Combes, F., English, J., Heald, G. H., Kamphuis, P., Koribalski, B. S., Meurer, G. R., Román, J., Sardone, A., Verdes-Montenegro, L., Bigiel, F., Brinks, E., Chemin, L., Fraternali, F., Jarrett, T., Kleiner, D., Maccagni, F. M., Pisano, D. J., Serra, P., Spekkens, K., Amram, P., Carignan, C., Dettmar, R-J., Gibson, B. K., Holwerda, B. W., Józsa, G. I. G, Lucero, D. M., Oosterloo, T. A., Ramaila, A. J. T., Ramatsoku, M., Sheth, K., Walter, F., Wong, O. I., Zijlstra, A. A., Bloemen, S., Groot, P. J., Poole, R. Le, Klein-Wolt, M., Körding, E. G., McBride, V. A., Paterson, K., Pieterse, D. L. A., Vreeswijk, P., and Woudt, P. A.
Subjects: Astrophysics - Astrophysics of Galaxies
Abstract: We present the results of three commissioning HI observations obtained with the MeerKAT radio telescope. These observations make up part of the preparation for the forthcoming MHONGOOSE nearby galaxy survey, which is a MeerKAT large survey project that will study the accretion of gas in galaxies and the link between gas and star formation. We used the available HI data sets, along with ancillary data at other wavelengths, to study the morphology of the MHONGOOSE sample galaxy, ESO 302-G014, which is a nearby gas-rich dwarf galaxy. We find that ESO 302-G014 has a lopsided, asymmetric outer disc with a low column density. In addition, we find a tail or filament of HI clouds extending away from the galaxy, as well as an isolated HI cloud some 20 kpc to the south of the galaxy. We suggest that these features indicate a minor interaction with a low-mass galaxy. Optical imaging shows a possible dwarf galaxy near the tail, but based on the current data, we cannot confirm any association with ESO 302-G014. Nonetheless, an interaction scenario with some kind of low-mass companion is still supported by the presence of a significant amount of molecular gas, which is almost equal to the stellar mass, and a number of prominent stellar clusters, which suggest recently triggered star formation. These data show that MeerKAT produces exquisite imaging data. The forthcoming full-depth survey observations of ESO 302-G014 and other sample galaxies will, therefore, offer insights into the fate of neutral gas as it moves from the intergalactic medium onto galaxies., Comment: Accepted for publication in Astronomy and Astrophysics
Published: 2020
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77. Sparsification Lower Bounds for List $H$-Coloring

Author: Chen, Hubie, Jansen, Bart M. P., Okrasa, Karolina, Pieterse, Astrid, and Rzążewski, Paweł
Subjects: Computer Science - Computational Complexity
Abstract: We investigate the List $H$-Coloring problem, the generalization of graph coloring that asks whether an input graph $G$ admits a homomorphism to the undirected graph $H$ (possibly with loops), such that each vertex $v \in V(G)$ is mapped to a vertex on its list $L(v) \subseteq V(H)$. An important result by Feder, Hell, and Huang [JGT 2003] states that List $H$-Coloring is polynomial-time solvable if $H$ is a so-called bi-arc graph, and NP-complete otherwise. We investigate the NP-complete cases of the problem from the perspective of polynomial-time sparsification: can an $n$-vertex instance be efficiently reduced to an equivalent instance of bitsize $O(n^{2-\varepsilon})$ for some $\varepsilon > 0$? We prove that if $H$ is not a bi-arc graph, then List $H$-Coloring does not admit such a sparsification algorithm unless $NP \subseteq coNP/poly$. Our proofs combine techniques from kernelization lower bounds with a study of the structure of graphs $H$ which are not bi-arc graphs., Comment: Accepted to ISAAC 2020
Published: 2020

78. Deep-sea deployment of the KM3NeT neutrino telescope detection units by self-unrolling

Author: The KM3NeT Collaboration, Aiello, S., Albert, A., Garre, S. Alves, Aly, Z., Ameli, F., Anassontzis, E. G., Andre, M., Androulakis, G., Anghinolfi, M., Anguita, M., Anton, G., Ardid, M., Aublin, J., Bagatelas, C., Bakker, R., Barbarino, G., Baret, B., Pree, S. Basegmez du, Bendahman, M., Berbeen, E., Berg, A. M. van den, Bertin, V., Biagi, S., Billault, M., Bissinger, M., Boettcher, M., Boumaaza, J., Bouta, M., Bouwhuis, M., Bozza, C., Brânzaş, H., Bruijn, R., Brunner, J., Buis, E., Buompane, R., Busto, J., Cacopardo, G., Caiffi, B., Caillat, L., Calvo, D., Capone, A., Carretero, V., Castaldi, P., Celli, S., Chabab, M., Chau, N., Chen, A., Cherubini, S., Chiarella, V., Chiarusi, T., Circella, M., Cocimano, R., Coelho, J. A. B., Coleiro, A., Molla, M. Colomer, Colonges, S., Coniglione, R., Corredoira, I., Cosquer, A., Coyle, P., Creusot, A., Cuttone, G., D'Amato, C., D'Onofrio, A., Dallier, R., De Palma, M., Di Palma, I., Díaz, A. F., Diego-Tortosa, D., Distefano, C., Domi, A., Donà, R., Donzau, C., Dornic, D., Dörr, M., Drouhin, D., Eberl, T., Eddyamoui, A., van Eeden, T., van Eijk, D., Bojaddaini, I. El, Elsaesser, D., Enzenhöfer, A., Espinosa, V., Fermani, P., Ferrara, G., Filipović, M. D., Filippini, F., Fusco, L. A., Gabella, O., Gal, T., Soto, A. Garcia, Garufi, F., Gatelet, Y., Geißelbrecht, N., Gialanella, L., Giorgio, E., Gostiaux, L., Gozzini, S. R., Gracia, R., Graf, K., Grasso, D., Grella, G., Grmek, A., Guderian, D., Guidii, C., Hallmann, S., Hamdaoui, H., van Haren, H., van Heerwaarden, J., Heijboer, A., Hekaloa, A., Henry, S., Hernández-Rey, J. J., Hillebrand, T., Hofestädt, J., Huang, F., Ibnsalih, W. Idrissi, Ilioni, A., Illuminati, G., James, C. W., de Jong, M., de Jong, P., Jung, B. J., Kadler, M., Kalaczyński, P., Kalekin, O., Katz, U. F., Chowdhury, N. R. Khan, Kistauri, G., van der Knaap, F., Koffeman, E. N., Kooijman, P., Kouchner, A., Kreter, M., Kulikovskiy, V., Laan, M., Lahmann, R., Lamare, P., Larosa, G., Laurence, J., Breton, R. Le, Leonardi, O., Leone, F., Leonora, E., Levi, G., Lincetto, M., Clark, M. Lindsey, Lipreau, T., Longhitano, F., LopezCotoa, D., Maderer, L., Mańczak, J., Mannheim, K., Margiotta, A., Marinelli, A., Markou, C., Martin, L., Martínez-Mora, J. A., Martini, A., Marzaioli, F., Mastroianni, S., Mazzou, S., Melis, K. W., Miele, G., Migliozzi, P., Migneco, E., Mijakowski, P., Miranda, L. S., Mollo, C. M., Mongelli, M., Morganti, M., Moser, M., Moussa, A., Muller, R., Pérez, D. Muñoz, Musumeci, M., Nauta, L., Navas, S., Nicolau, C. A., Fearraigh, B. Ó, O'Sullivan, M., Organokov, M., Orlando, A., González, J. Palacios, Papalashvili, G., Papaleo, R., Pastore, C., Păun, A. M., Păvălaş, G. E., Pellegrino, C., Perrin-Terrin, M., Piattelli, P., Pieterse, C., Pikounis, K., Pisanti, O., Poirè, C., Popa, V., Pradier, T., Pühlhofer, G., Pulvirenti, S., Rabyang, O., Raffaelli, F., Randazzo, N., Razzaque, S., Real, D., Reck, S., Riccobene, G., Richer, M., Rivoire, S., Rovelli, A., Greus, F. Salesa, Samtleben, D. F. E., Losa, A. Sánchez, Sanguineti, M., Santangelo, A., Santonocito, D., Sapienza, P., Schnabel, J., Schumann, J., Seneca, J., Sgura, I., Shanidze, R., Sharma, A., Simeone, F., Sinopoulou, A., Spisso, B., Spurio, M., Stavropoulos, D., Steijger, J., Stellacci, S. M., Taiutii, M., Tayalati, Y., Tenllado, E., Tézier, D., Thakore, T., Tingay, S., Tzamariudaki, E., Tzanetatos, D., Van Elewyck, V., Vasileiadis, G., Versari, F., Viola, S., Vivolo, D., de Wasseige, G., Wilms, J., Wojaczyński, R., de Wolf, E., Zavatarelli, S., Zegarelli, A., Zito, D., Zornoza, J. D., Zúñiga, J., and Zywucka, N.
Subjects: Astrophysics - Instrumentation and Methods for Astrophysics
Abstract: KM3NeT is a research infrastructure being installed in the deep Mediterranean Sea. It will house a neutrino telescope comprising hundreds of networked moorings - detection units or strings equipped with optical instrumentation to detect the Cherenkov radiation generated by charged particles from neutrino-induced collisions in its vicinity. In comparison to moorings typically used for oceanography, several key features of the KM3NeT string are different: the instrumentation is contained in transparent and thus unprotected glass spheres; two thin Dyneema ropes are used as strength members; and a thin delicate backbone tube with fibre-optics and copper wires for data and power transmission, respectively, runs along the full length of the mooring. Also, compared to other neutrino telescopes such as ANTARES in the Mediterranean Sea and GVD in Lake Baikal, the KM3NeT strings are more slender to minimise the amount of material used for support of the optical sensors. Moreover, the rate of deploying a large number of strings in a period of a few years is unprecedented. For all these reasons, for the installation of the KM3NeT strings, a custom-made, fast deployment method was designed. Despite the length of several hundreds of metres, the slim design of the string allows it to be compacted into a small, re-usable spherical launching vehicle instead of deploying the mooring weight down from a surface vessel. After being lowered to the seafloor, the string unfurls to its full length with the buoyant launching vehicle rolling along the two ropes.The design of the vehicle, the loading with a string, and its underwater self-unrolling are detailed in this paper.
Published: 2020

79. Measuring HERA's primary beam in-situ: methodology and first results

Author: Nunhokee, Chuneeta D., Parsons, Aaron R., Kern, Nicholas S., Nikolic, Bojan, Pober, Jonathan C., Bernardi, Gianni, Carilli, Chris L., Abdurashidova, Zara, Aguirre, James E., Alexander, Paul, Ali, Zaki S., Balfour, Yanga, Beardsley, Adam P., Billings, Tashalee S., Bowman, Judd D., Bradley, Richard F., Burba, Jacob, Cheng, Carina, DeBoer, David R., Dexter, Matt, de~Lera~Acedo, Eloy, Dillon, Joshua S., Ewall-Wice, Aaron, Fagnoni, Nicolas, Fritz, Randall, Furlanetto, Steve R., Gale-Sides, Kingsley, Glendenning, Brian, Gorthi, Deepthi, Greig, Bradley, Grobbelaar, Jasper, Halday, Ziyaad, Hazelton, Bryna J., Hewitt, Jacqueline N., Jacobs, Daniel C., Julius, Austin, Kerrigan, Joshua, Kittiwisit, Piyanat, Kohn, Saul A., Kolopanis, Matthew, Lanman, Adam, La~Plante, Paul, Lekalake, Telalo, Liu, Adrian, MacMahon, David, Malan, Lourence, Malgas, Cresshim, Maree, Matthys, Martinot, Zachary E., Matsetela, Eunice, Mesinger, Andrei, Molewa, Mathakane, Morales, Miguel F., Mosiane, Tshegofalang, Neben, Abraham R., Patra, Nipanjana, Pieterse, Samantha, Razavi-Ghods, Nima, Ringuette, Jon, Robnett, James, Rosie, Kathryn, Sims, Peter, Smith, Craig, Syce, Angelo, Thyagarajan, Nithyanandan, Williams, Peter K. ~G., and Zheng, Haoxuan
Subjects: Astrophysics - Instrumentation and Methods for Astrophysics, Astrophysics - Cosmology and Nongalactic Astrophysics
Abstract: The central challenge in 21~cm cosmology is isolating the cosmological signal from bright foregrounds. Many separation techniques rely on the accurate knowledge of the sky and the instrumental response, including the antenna primary beam. For drift-scan telescopes such as the Hydrogen Epoch of Reionization Array \citep[HERA, ][]{DeBoer2017} that do not move, primary beam characterization is particularly challenging because standard beam-calibration routines do not apply \citep{Cornwell2005} and current techniques require accurate source catalogs at the telescope resolution. We present an extension of the method from \citet{Pober2012} where they use beam symmetries to create a network of overlapping source tracks that break the degeneracy between source flux density and beam response and allow their simultaneous estimation. We fit the beam response of our instrument using early HERA observations and find that our results agree well with electromagnetic simulations down to a -20~dB level in power relative to peak gain for sources with high signal-to-noise ratio. In addition, we construct a source catalog with 90 sources down to a flux density of 1.4~Jy at 151~MHz., Comment: 22 pages, 22 figures, accepted for publication in ApJ
Published: 2020
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80. Detection of Cosmic Structures using the Bispectrum Phase. II. First Results from Application to Cosmic Reionization Using the Hydrogen Epoch of Reionization Array

Author: Thyagarajan, Nithyanandan, Carilli, Chris L., Nikolic, Bojan, Kent, James, Mesinger, Andrei, Kern, Nicholas S., Bernardi, Gianni, Matika, Siyanda, Abdurashidova, Zara, Aguirre, James E., Alexander, Paul, Ali, Zaki S., Balfour, Yanga, Beardsley, Adam P., Billings, Tashalee S., Bowman, Judd D., Bradley, Richard F., Burba, Jacob, Carey, Steve, Cheng, Carina, DeBoer, David R., Dexter, Matt, Acedo, Eloy de Lera, Dillon, Joshua S., Ely, John, Ewall-Wice, Aaron, Fagnoni, Nicolas, Fritz, Randall, Furlanetto, Steven R., Gale-Sides, Kingsley, Glendenning, Brian, Gorthi, Deepthi, Greig, Bradley, Grobbelaar, Jasper, Halday, Ziyaad, Hazelton, Bryna J., Hewitt, Jacqueline N., Hickish, Jack, Jacobs, Daniel C., Julius, Austin, Kerrigan, Joshua, Kittiwisit, Piyanat, Kohn, Saul A., Kolopanis, Matthew, Lanman, Adam, La Plante, Paul, Lekalake, Telalo, Lewis, David, Liu, Adrian, MacMahon, David, Malan, Lourence, Malgas, Cresshim, Maree, Matthys, Martinot, Zachary E., Matsetela, Eunice, Molewa, Mathakane, Morales, Miguel F., Mosiane, Tshegofalang, Neben, Abraham R., Parsons, Aaron R., Patra, Nipanjana, Pieterse, Samantha, Pober, Jonathan C., Razavi-Ghods, Nima, Ringuette, Jon, Robnett, James, Rosie, Kathryn, Sims, Peter, Smith, Craig, Syce, Angelo, Williams, Peter K. G., and Zheng, Haoxuan
Subjects: Astrophysics - Cosmology and Nongalactic Astrophysics, Astrophysics - Instrumentation and Methods for Astrophysics
Abstract: Characterizing the epoch of reionization (EoR) at $z\gtrsim 6$ via the redshifted 21 cm line of neutral Hydrogen (HI) is critical to modern astrophysics and cosmology, and thus a key science goal of many current and planned low-frequency radio telescopes. The primary challenge to detecting this signal is the overwhelmingly bright foreground emission at these frequencies, placing stringent requirements on the knowledge of the instruments and inaccuracies in analyses. Results from these experiments have largely been limited not by thermal sensitivity but by systematics, particularly caused by the inability to calibrate the instrument to high accuracy. The interferometric bispectrum phase is immune to antenna-based calibration and errors therein, and presents an independent alternative to detect the EoR HI fluctuations while largely avoiding calibration systematics. Here, we provide a demonstration of this technique on a subset of data from the Hydrogen Epoch of Reionization Array (HERA) to place approximate constraints on the brightness temperature of the intergalactic medium (IGM). From this limited data, at $z=7.7$ we infer "$1\sigma$" upper limits on the IGM brightness temperature to be $\le 316$ "pseudo" mK at $\kappa_\parallel=0.33$ "pseudo" $h$ Mpc$^{-1}$ (data-limited) and $\le 1000$ "pseudo" mK at $\kappa_\parallel=0.875$ "pseudo" $h$ Mpc$^{-1}$ (noise-limited). The "pseudo" units denote only an approximate and not an exact correspondence to the actual distance scales and brightness temperatures. By propagating models in parallel to the data analysis, we confirm that the dynamic range required to separate the cosmic HI signal from the foregrounds is similar to that in standard approaches, and the power spectrum of the bispectrum phase is still data-limited (at $\gtrsim 10^6$ dynamic range) indicating scope for further improvement in sensitivity as the array build-out continues., Comment: 22 pages, 12 figures (including sub-figures). Published in PhRvD. Abstract may be slightly abridged compared to the actual manuscript due to length limitations on arXiv
Published: 2020
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81. Approximate Turing Kernelization for Problems Parameterized by Treewidth

Author: Hols, Eva-Maria C., Kratsch, Stefan, and Pieterse, Astrid
Subjects: Computer Science - Data Structures and Algorithms, Computer Science - Computational Complexity
Abstract: We extend the notion of lossy kernelization, introduced by Lokshtanov et al. [STOC 2017], to approximate Turing kernelization. An $\alpha$-approximate Turing kernel for a parameterized optimization problem is a polynomial-time algorithm that, when given access to an oracle that outputs $c$-approximate solutions in $O(1)$ time, obtains an $(\alpha \cdot c)$-approximate solution to the considered problem, using calls to the oracle of size at most $f(k)$ for some function $f$ that only depends on the parameter. Using this definition, we show that Independent Set parameterized by treewidth $\ell$ has a $(1+\varepsilon)$-approximate Turing kernel with $O(\frac{\ell^2}{\varepsilon})$ vertices, answering an open question posed by Lokshtanov et al. [STOC 2017]. Furthermore, we give $(1+\varepsilon)$-approximate Turing kernels for the following graph problems parameterized by treewidth: Vertex Cover, Edge Clique Cover, Edge-Disjoint Triangle Packing and Connected Vertex Cover. We generalize the result for Independent Set and Vertex Cover, by showing that all graph problems that we will call "friendly" admit $(1+\varepsilon)$-approximate Turing kernels of polynomial size when parameterized by treewidth. We use this to obtain approximate Turing kernels for Vertex-Disjoint $H$-packing for connected graphs $H$, Clique Cover, Feedback Vertex Set and Edge Dominating Set.
Published: 2020

82. Event reconstruction for KM3NeT/ORCA using convolutional neural networks

Author: Aiello, Sebastiano, Albert, Arnauld, Garre, Sergio Alves, Aly, Zineb, Ameli, Fabrizio, Andre, Michel, Androulakis, Giorgos, Anghinolfi, Marco, Anguita, Mancia, Anton, Gisela, Ardid, Miquel, Aublin, Julien, Bagatelas, Christos, Barbarino, Giancarlo, Baret, Bruny, Pree, Suzan Basegmez du, Bendahman, Meriem, Berbee, Edward, Bertin, Vincent, Biagi, Simone, Biagioni, Andrea, Bissinger, Matthias, Boettcher, Markus, Boumaaza, Jihad, Bouta, Mohammed, Bouwhuis, Mieke, Bozza, Cristiano, Branzas, Horea, Bruijn, Ronald, Brunner, Jürgen, Buis, Ernst-Jan, Buompane, Raffaele, Busto, Jose, Caiffi, Barbara, Calvo, David, Capone, Antonio, Carretero, Víctor, Castaldi, Paolo, Celli, Silvia, Chabab, Mohamed, Chau, Nhan, Chen, Andrew, Cherubini, Silvio, Chiarella, Vitaliano, Chiarusi, Tommaso, Circella, Marco, Cocimano, Rosanna, Coelho, Joao, Coleiro, Alexis, Molla, Marta Colomer, Coniglione, Rosa, Coyle, Paschal, Creusot, Alexandre, Cuttone, Giacomo, D'Onofrio, Antonio, Dallier, Richard, de Jong, Maarten, de Jong, Paul, De Palma, Mauro, de Wasseige, Gwenhaël, de Wolf, Els, Di Palma, Irene, Diaz, Antonio, Diego-Tortosa, Dídac, Distefano, Carla, Domi, Alba, Donà, Roberto, Donzaud, Corinne, Dornic, Damien, Dörr, Manuel, Drouhin, Doriane, Eberl, Thomas, Bojaddaini, Imad El, Elsaesser, Dominik, Enzenhöfer, Alexander, Fermani, Paolo, Ferrara, Giovanna, Filipovic, Miroslav, Filippini, Francesco, Fusco, Luigi Antonio, Gabella, Omar, Gal, Tamas, Soto, Alfonso Andres Garcia, Garufi, Fabio, Gatelet, Yoann, Geißelbrecht, Nicole, Gialanella, Lucio, Giorgio, Emidio, Gozzini, Sara Rebecca, Gracia, Rodrigo, Graf, Kay, Grasso, Dario, Grella, Giuseppe, Guidi, Carlo, Hallmann, Steffen, Hamdaoui, Hassane, Heijboer, Aart, Hekalo, Amar, Hernandez-Rey, Juan-Jose, Hofestädt, Jannik, Huang, Feifei, Ibnsalih, Walid Idrissi, Illuminati, Giulia, James, Clancy, Jung, Bouke Jisse, Kadler, Matthias, Kalaczyński, Piotr, Kalekin, Oleg, Katz, Uli, Chowdhury, Nafis Rezwan Khan, Kistauri, Giorgi, Koffeman, Els, Kooijman, Paul, Kouchner, Antoine, Kreter, Michael, Kulikovskiy, Vladimir, Lahmann, Robert, Larosa, Giuseppina, Breton, Remy Le, Leonardi, Ornella, Leone, Francesco, Leonora, Emanuele, Levi, Giuseppe, Lincetto, Massimiliano, Clark, Miles Lindsey, Lipreau, Thomas, Lonardo, Alessandro, Longhitano, Fabio, Coto, Daniel Lopez, Maderer, Lukas, Mańczak, Jerzy, Mannheim, Karl, Margiotta, Annarita, Marinelli, Antonio, Markou, Christos, Martin, Lilian, Martínez-Mora, Juan Antonio, Martini, Agnese, Marzaioli, Fabio, Mastroianni, Stefano, Mazzou, Safaa, Melis, Karel, Miele, Gennaro, Migliozzi, Pasquale, Migneco, Emilio, Mijakowski, Piotr, Palacios, Luis Salvador Miranda, Mollo, Carlos Maximiliano, Morganti, Mauro, Moser, Michael, Moussa, Abdelilah, Muller, Rasa, Musumeci, Mario, Nauta, Lodewijk, Navas, Sergio, Nicolau, Carlo Alessandro, Fearraigh, Brían Ó, Organokov, Mukharbek, Orlando, Angelo, Papalashvili, Gogita, Papaleo, Riccardo, Pastore, Cosimo, Paun, Alice, Pavalas, Gabriela Emilia, Pellegrino, Carmelo, Perrin-Terrin, Mathieu, Piattelli, Paolo, Pieterse, Camiel, Pikounis, Konstantinos, Pisanti, Ofelia, Poirè, Chiara, Popa, Vlad, Post, Maarten, Pradier, Thierry, Pühlhofer, Gerd, Pulvirenti, Sara, Rabyang, Omphile, Raffaelli, Fabrizio, Randazzo, Nunzio, Rapicavoli, Antonio, Razzaque, Soebur, Real, Diego, Reck, Stefan, Riccobene, Giorgio, Richer, Marc, Rivoire, Stephane, Rovelli, Alberto, Greus, Francisco Salesa, Samtleben, Dorothea Franziska Elisabeth, Losa, Agustín Sánchez, Sanguineti, Matteo, Santangelo, Andrea, Santonocito, Domenico, Sapienza, Piera, Schnabel, Jutta, Seneca, Jordan, Sgura, Irene, Shanidze, Rezo, Sharma, Ankur, Simeone, Francesco, Sinopoulou, Anna, Spisso, Bernardino, Spurio, Maurizio, Stavropoulos, Dimitris, Steijger, Jos, Stellacci, Simona Maria, Taiuti, Mauro, Tayalati, Yahya, Tenllado, Enrique, Thakore, Tarak, Tingay, Steven, Tzamariudaki, Ekaterini, Tzanetatos, Dimitrios, Berg, Ad van den, van der Knaap, Frits, van Eijk, Daan, Van Elewyck, Véronique, van Haren, Hans, Vannoye, Godefroy, Vasileiadis, George, Versari, Federico, Viola, Salvatore, Vivolo, Daniele, Wilms, Joern, Wojaczyński, Rafał, Zaborov, Dmitry, Zavatarelli, Sandra, Zegarelli, Angela, Zito, Daniele, Zornoza, Juan-de-Dios, Zúñiga, Juan, and Zywucka, Natalia
Subjects: Astrophysics - Instrumentation and Methods for Astrophysics, High Energy Physics - Experiment, Physics - Instrumentation and Detectors
Abstract: The KM3NeT research infrastructure is currently under construction at two locations in the Mediterranean Sea. The KM3NeT/ORCA water-Cherenkov neutrino detector off the French coast will instrument several megatons of seawater with photosensors. Its main objective is the determination of the neutrino mass ordering. This work aims at demonstrating the general applicability of deep convolutional neural networks to neutrino telescopes, using simulated datasets for the KM3NeT/ORCA detector as an example. To this end, the networks are employed to achieve reconstruction and classification tasks that constitute an alternative to the analysis pipeline presented for KM3NeT/ORCA in the KM3NeT Letter of Intent. They are used to infer event reconstruction estimates for the energy, the direction, and the interaction point of incident neutrinos. The spatial distribution of Cherenkov light generated by charged particles induced in neutrino interactions is classified as shower- or track-like, and the main background processes associated with the detection of atmospheric neutrinos are recognized. Performance comparisons to machine-learning classification and maximum-likelihood reconstruction algorithms previously developed for KM3NeT/ORCA are provided. It is shown that this application of deep convolutional neural networks to simulated datasets for a large-volume neutrino telescope yields competitive reconstruction results and performance improvements with respect to classical approaches.
Published: 2020
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83. Foreground modelling via Gaussian process regression: an application to HERA data

Author: Ghosh, Abhik, Mertens, Florent, Bernardi, Gianni, Santos, Mário G., Kern, Nicholas S., Carilli, Christopher L., Grobler, Trienko L., Koopmans, Léon V. E., Jacobs, Daniel C., Liu, Adrian, Parsons, Aaron R., Morales, Miguel F., Aguirre, James E., Dillon, Joshua S., Hazelton, Bryna J., Smirnov, Oleg M., Gehlot, Bharat K., Matika, Siyanda, Alexander, Paul, Ali, Zaki S., Beardsley, Adam P., Benefo, Roshan K., Billings, Tashalee S., Bowman, Judd D., Bradley, Richard F., Cheng, Carina, Chichura, Paul M., DeBoer, David R., Acedo, Eloy de Lera, Ewall-Wice, Aaron, Fadana, Gcobisa, Fagnoni, Nicolas, Fortino, Austin F., Fritz, Randall, Furlanetto, Steve R., Gallardo, Samavarti, Glendenning, Brian, Gorthi, Deepthi, Greig, Bradley, Grobbelaar, Jasper, Hickish, Jack, Josaitis, Alec, Julius, Austin, Igarashi, Amy S., Kariseb, MacCalvin, Kohn, Saul A., Kolopanis, Matthew, Lekalake, Telalo, Loots, Anita, MacMahon, David, Malan, Lourence, Malgas, Cresshim, Maree, Matthys, Martinot, Zachary E., Mathison, Nathan, Matsetela, Eunice, Mesinger, Andrei, Neben, Abraham R., Nikolic, Bojan, Nunhokee, Chuneeta D., Patra, Nipanjana, Pieterse, Samantha, Razavi-Ghods, Nima, Ringuette, Jon, Robnett, James, Rosie, Kathryn, Sell, Raddwine, Smith, Craig, Syce, Angelo, Tegmark, Max, Thyagarajan, Nithyanandan, Williams, Peter K. G., and Zheng, Haoxuan
Subjects: Astrophysics - Cosmology and Nongalactic Astrophysics
Abstract: The key challenge in the observation of the redshifted 21-cm signal from cosmic reionization is its separation from the much brighter foreground emission. Such separation relies on the different spectral properties of the two components, although, in real life, the foreground intrinsic spectrum is often corrupted by the instrumental response, inducing systematic effects that can further jeopardize the measurement of the 21-cm signal. In this paper, we use Gaussian Process Regression to model both foreground emission and instrumental systematics in $\sim 2$ hours of data from the Hydrogen Epoch of Reionization Array. We find that a simple co-variance model with three components matches the data well, giving a residual power spectrum with white noise properties. These consist of an "intrinsic" and instrumentally corrupted component with a coherence-scale of 20 MHz and 2.4 MHz respectively (dominating the line of sight power spectrum over scales $k_{\parallel} \le 0.2$ h cMpc$^{-1}$) and a baseline dependent periodic signal with a period of $\sim 1$ MHz (dominating over $k_{\parallel} \sim 0.4 - 0.8$h cMpc$^{-1}$) which should be distinguishable from the 21-cm EoR signal whose typical coherence-scales is $\sim 0.8$ MHz., Comment: 15 pages, 15 figures, 1 table, Accepted to MNRAS
Published: 2020
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84. Elucidation of familial relationships using hair shaft proteomics

Author: Karim, Noreen, Plott, Tempest J, Durbin-Johnson, Blythe P, Rocke, David M, Salemi, Michelle, Phinney, Brett S, Goecker, Zachary C, Pieterse, Marc JM, Parker, Glendon J, and Rice, Robert H
Subjects: Biological Sciences, Genetics, Human Genome, Biotechnology, 1.1 Normal biological development and functioning, Hair, Humans, Mass Spectrometry, Peptides, Polymorphism, Single Nucleotide, Proteomics, Proteomic profiling, Genetically variant peptides, Human hair, Forensic investigation, Relationship testing, Mathematical Sciences, Law and Legal Studies, Legal & Forensic Medicine, Biological sciences, Law and legal studies, Mathematical sciences
Abstract: This study examines the potential of hair shaft proteomic analysis to delineate genetic relatedness. Proteomic profiling and amino acid sequence analysis provide information for quantitative and statistically-based analysis of individualization and sample similarity. Protein expression levels are a function of cell-specific transcriptional and translational programs. These programs are greatly influenced by an individual's genetic background, and are therefore influenced by familial relatedness as well as ancestry and genetic disease. Proteomic profiles should therefore be more similar among related individuals than unrelated individuals. Likewise, profiles of genetically variant peptides that contain single amino acid polymorphisms, the result of non-synonymous SNP alleles, should behave similarly. The proteomically-inferred SNP alleles should also provide a basis for calculation of combined paternity and sibship indices. We test these hypotheses using matching proteomic and genetic datasets from a family of two adults and four siblings, one of which has a genetic condition that perturbs hair structure and properties. We demonstrate that related individuals, compared to those who are unrelated, have more similar proteomic profiles, profiles of genetically variant peptides and higher combined paternity indices and combined sibship indices. This study builds on previous analyses of hair shaft protein profiling and genetically variant peptide profiles in different real-world scenarios including different human hair shaft body locations and pigmentation status. It also validates the inclusion of proteomic information with other biomolecular substrates in forensic hair shaft analysis, including mitochondrial and nuclear DNA.
Published: 2021

85. Parag Khanna: The Future Is Asian: Commerce, Conflict, and Culture in the 21st Century

Author: Pieterse, Jan Nederveen
Published: 2021

86. Faculty-Students Online Communication Channels

Author: Meishar-Tal, Hagit and Pieterse, Efrat
Abstract: In recent years, we have witnessed a significant expansion of the communication channels available to lecturers and students. The purpose of this study is to examine the considerations guiding faculty members in choosing the communication channels they offer their students and the connection between the communication channel chosen and personal and organizational characteristics. The study was conducted using a questionnaire distributed among lecturers through public distribution lists and social networks. A total of 128 respondents completed the questionnaire. It was found that the lecturers' use of the various communication channels available to them was conservative, i.e., the leading channels in use were formal communication (e-mail, face-to-face meetings, and course websites). The lecturers made very little use of personal communication channels and rarely used social media. It was also found that organizational climate, personality characteristics, and the perception of the lecturers' role were related to the use of personal and social communication channels. [For the complete proceedings, see ED601080.]
Published: 2019

87. gSeaGen: the KM3NeT GENIE-based code for neutrino telescopes

Author: Aiello, Sebastiano, Albert, Arnauld, Garre, Sergio Alves, Aly, Zineb, Ameli, Fabrizio, Andre, Michel, Androulakis, Giorgos, Anghinolfi, Marco, Anguita, Mancia, Anton, Gisela, Ardid, Miquel, Aublin, Julien, Bagatelas, Christos, Barbarino, Giancarlo, Baret, Bruny, Pree, Suzan Basegmez du, Bendahman, Meriem, Berbee, Edward, Bertin, Vincent, Biagi, Simone, Biagioni, Andrea, Bissinger, Matthias, Boettcher, Markus, Boumaaza, Jihad, Bourret, Simon, Bouta, Mohammed, Bouwhuis, Mieke, Bozza, Cristiano, Branzas, Horea, Bruchner, Marc, Bruijn, Ronald, Brunner, Jürgen, Buis, Ernst-Jan, Buompane, Raffaele, Busto, Jose, Calvo, David, Capone, Antonio, Carretero, Víctor, Castaldi, Paolo, Celli, Silvia, Chabab, Mohamed, Chau, Nhan, Chen, Andrew, Cherubini, Silvio, Chiarella, Vitaliano, Chiarusi, Tommaso, Circella, Marco, Cocimano, Rosanna, Coelho, Joao, Coleiro, Alexis, Molla, Marta Colomer, Coniglione, Rosa, Corredoira, Imanol, Coyle, Paschal, Creusot, Alexandre, Cuttone, Giacomo, D'Onofrio, Antonio, Dallier, Richard, de Jong, Maarten, de Jong, Paul, De Palma, Mauro, de Wasseige, Gwenhaël, de Wolf, Els, Di Palma, Irene, Diaz, Antonio, Diego-Tortosa, Dídac, Distefano, Carla, Domi, Alba, Donà, Roberto, Donzaud, Corinne, Dornic, Damien, Dörr, Manuel, Drouhin, Doriane, Durocher, Mora, Eberl, Thomas, Bojaddaini, Imad El, Elsaesser, Dominik, Enzenhöfer, Alexander, Fermani, Paolo, Ferrara, Giovanna, Filipovic, Miroslav, Filippini, Francesco, Franco, Antonio, Fusco, Luigi Antonio, Gabella, Omar, Gal, Tamas, Soto, Alfonso Andres Garcia, Garufi, Fabio, Gatelet, Yoann, Geißelbrecht, Nicole, Gialanella, Lucio, Giorgio, Emidio, Gozzini, Sara Rebecca, Gracia, Rodrigo, Graf, Kay, Grasso, Dario, Grégoire, Timothée, Grella, Giuseppe, Guidi, Carlo, Hallmann, Steffen, Hamdaoui, Hassane, Heijboer, Aart, Hekalo, Amar, Hernandez-Rey, Juan-Jose, Hofestädt, Jannik, Ibnsalih, Walid Idrissi, Illuminati, Giulia, James, Clancy, Jung, Bouke Jisse, Kadler, Matthias, Kalaczyński, Piotr, Kalekin, Oleg, Katz, Uli, Chowdhury, Nafis Rezwan Khan, Koffeman, Els, Kooijman, Paul, Kouchner, Antoine, Kreter, Michael, Kulikovskiy, Vladimir, Lahmann, Robert, Larosa, Giuseppina, Breton, Remy Le, Leonardi, Ornella, Leone, Francesco, Leonora, Emanuele, Levi, Giuseppe, Lincetto, Massimiliano, Clark, Miles Lindsey, Lipreau, Thomas, Lonardo, Alessandro, Longhitano, Fabio, Coto, Daniel Lopez, Mańczak, Jerzy, Mannheim, Karl, Margiotta, Annarita, Marinelli, Antonio, Markou, Christos, Martin, Lilian, Martínez-Mora, Juan Antonio, Martini, Agnese, Marzaioli, Fabio, Mastroianni, Stefano, Mazzou, Safaa, Melis, Karel, Miele, Gennaro, Migliozzi, Pasquale, Migneco, Emilio, Mijakowski, Piotr, Palacios, Luis Salvador Miranda, Modebadze, Zurab, Mollo, Carlos Maximiliano, Morganti, Mauro, Moser, Michael, Moussa, Abdelilah, Muller, Rasa, Musumeci, Mario, Nauta, Lodewijk, Navas, Sergio, Nicolau, Carlo Alessandro, Fearraigh, Brían Ó, Organokov, Mukharbek, Orlando, Angelo, Papalashvili, Gogita, Papaleo, Riccardo, Pastore, Cosimo, Paun, Alice, Pavalas, Gabriela Emilia, Pellegrino, Carmelo, Perrin-Terrin, Mathieu, Piattelli, Paolo, Pieterse, Camiel, Pikounis, Konstantinos, Pisanti, Ofelia, Poirè, Chiara, Popa, Vlad, Post, Maarten, Pradier, Thierry, Pühlhofer, Gerd, Pulvirenti, Sara, Quinn, Liam, Rabyang, Omphile, Raffaelli, Fabrizio, Randazzo, Nunzio, Rapicavoli, Antonio, Razzaque, Soebur, Real, Diego, Reck, Stefan, Reubelt, Jonas, Riccobene, Giorgio, Richer, Marc, Rivoire, Stephane, Rovelli, Alberto, Greus, Francisco Salesa, Samtleben, Dorothea Franziska Elisabeth, Losa, Agustín Sánchez, Sanguineti, Matteo, Santangelo, Andrea, Santonocito, Domenico, Sapienza, Piera, Schnabel, Jutta, Sciacca, Virginia, Seneca, Jordan, Sgura, Irene, Shanidze, Rezo, Sharma, Ankur, Simeone, Francesco, Sinopoulou, Anna, Spisso, Bernardino, Spurio, Maurizio, Stavropoulos, Dimitris, Steijger, Jos, Stellacci, Simona Maria, Taiuti, Mauro, Tayalati, Yahya, Tenllado, Enrique, Thakore, Tarak, Tingay, Steven, Tzamariudaki, Ekaterini, Tzanetatos, Dimitrios, Berg, Ad van den, van der Knaap, Frits, van Eijk, Daan, Van Elewyck, Véronique, Vannoye, Godefroy, Vasileiadis, George, Versari, Federico, Viola, Salvatore, Vivolo, Daniele, Wilms, Joern, Wojaczyński, Rafał, Zaborov, Dmitry, Zavatarelli, Sandra, Zegarelli, Angela, Zornoza, Juan-de-Dios, Zúñiga, Juan, and Zywucka, Natalia
Subjects: Astrophysics - Instrumentation and Methods for Astrophysics
Abstract: The gSeaGen code is a GENIE-based application developed to efficiently generate high statistics samples of events, induced by neutrino interactions, detectable in a neutrino telescope. The gSeaGen code is able to generate events induced by all neutrino flavours, considering topological differences between track-type and shower-like events. Neutrino interactions are simulated taking into account the density and the composition of the media surrounding the detector. The main features of gSeaGen are presented together with some examples of its application within the KM3NeT project., Comment: 45 pages, 10 figures
Published: 2020
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88. Redundant-Baseline Calibration of the Hydrogen Epoch of Reionization Array

Author: Dillon, Joshua S., Lee, Max, Ali, Zaki S., Parsons, Aaron R., Orosz, Naomi, Nunhokee, Chuneeta Devi, La Plante, Paul, Beardsley, Adam P., Kern, Nicholas S., Abdurashidova, Zara, Aguirre, James E., Alexander, Paul, Balfour, Yanga, Bernardi, Gianni, Billings, Tashalee S., Bowman, Judd D., Bradley, Richard F., Bull, Phil, Burba, Jacob, Carey, Steve, Carilli, Chris L., Cheng, Carina, DeBoer, David R., Dexter, Matt, Acedo, Eloy de Lera, Ely, John, Ewall-Wice, Aaron, Fagnoni, Nicolas, Fritz, Randall, Furlanetto, Steven R., Gale-Sides, Kingsley, Glendenning, Brian, Gorthi, Deepthi, Greig, Bradley, Grobbelaar, Jasper, Halday, Ziyaad, Hazelton, Bryna J., Hewitt, Jacqueline N., Hickish, Jack, Jacobs, Daniel C., Julius, Austin, Kerrigan, Joshua, Kittiwisit, Piyanat, Kohn, Saul A., Kolopanis, Matthew, Lanman, Adam, Lekalake, Telalo, Lewis, David, Liu, Adrian, Ma, Yin-Zhe, MacMahon, David, Malan, Lourence, Malgas, Cresshim, Maree, Matthys, Martinot, Zachary E., Matsetela, Eunice, Mesinger, Andrei, Molewa, Mathakane, Morales, Miguel F., Mosiane, Tshegofalang, Murray, Steven, Neben, Abraham R., Nikolic, Bojan, Pascua, Robert, Patra, Nipanjana, Pieterse, Samantha, Pober, Jonathan C., Razavi-Ghods, Nima, Ringuette, Jon, Robnett, James, Rosie, Kathryn, Santos, Mario G., Sims, Peter, Smith, Craig, Syce, Angelo, Tegmark, Max, Thyagarajan, Nithyanandan, Williams, Peter K. G., and Zheng, Haoxuan
Subjects: Astrophysics - Instrumentation and Methods for Astrophysics, Astrophysics - Cosmology and Nongalactic Astrophysics
Abstract: In 21 cm cosmology, precision calibration is key to the separation of the neutral hydrogen signal from very bright but spectrally-smooth astrophysical foregrounds. The Hydrogen Epoch of Reionization Array (HERA), an interferometer specialized for 21 cm cosmology and now under construction in South Africa, was designed to be largely calibrated using the self-consistency of repeated measurements of the same interferometric modes. This technique, known as "redundant-baseline calibration" resolves most of the internal degrees of freedom in the calibration problem. It assumes, however, on antenna elements with identical primary beams placed precisely on a redundant grid. In this work, we review the detailed implementation of the algorithms enabling redundant-baseline calibration and report results with HERA data. We quantify the effects of real-world non-redundancy and how they compare to the idealized scenario in which redundant measurements differ only in their noise realizations. Finally, we study how non-redundancy can produce spurious temporal structure in our calibration solutions--both in data and in simulations--and present strategies for mitigating that structure., Comment: 24 Pages, 19 Figures. Updated to match the accepted MNRAS version
Published: 2020
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89. A spectroscopic, photometric, polarimetric and radio study of the eclipsing polar UZ Fornacis: the first simultaneous SALT and MeerKAT observations

Author: Khangale, Zwidofhelangani N., Potter, Stephen B., Woudt, Patrick A., Buckley, David A. H., Semena, Andrey N., Kotze, Enrico J., Groenewald, Danièl N., Hewitt, Dante M., Pretorius, Margaretha L., Fender, Rob P., Groot, Paul, Bloemen, Steven, Klein-Wolt, Marc, Körding, Elmar, Poole, Rudolf Le, McBride, Vanessa A., Townsend, Lee, Paterson, Kerry, Pieterse, Danielle L. A., and Vreeswijk, Paul M.
Subjects: Astrophysics - Solar and Stellar Astrophysics, Astrophysics - High Energy Astrophysical Phenomena, Astrophysics - Instrumentation and Methods for Astrophysics
Abstract: We present phase-resolved spectroscopy, photometry and circular spectropolarimetry of the eclipsing polar UZ Fornacis. Doppler tomography of the strongest emission lines using the inside-out projection revealed the presence of three emission regions: from the irradiated face of the secondary star, the ballistic stream and the threading region, and the magnetically confined accretion stream. The total intensity spectrum shows broad emission features and a continuum that rises in the blue. The circularly polarized spectrum shows the presence of three cyclotron emission harmonics at $\sim$4500 \AA{}, 6000 \AA{} and 7700 \AA{}, corresponding to harmonic numbers 4, 3, and 2, respectively. These features are dominant before the eclipse and disappear after the eclipse. The harmonics are consistent with a magnetic field strength of $\sim$57 MG. We also present phase-resolved circular and linear photopolarimetry to complement the spectropolarimetry around the times of eclipse. MeerKAT radio observations show a faint source which has a peak flux density of 30.7 $\pm$ 5.4 $\mu$Jy/beam at 1.28 GHz at the position of UZ For., Comment: Accepted on MNRAS
Published: 2020
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90. Understanding the HERA Phase i receiver system with simulations and its impact on the detectability of the EoR delay power spectrum

Author: Fagnoni, N, De Lera Acedo, E, Deboer, DR, Abdurashidova, Z, Aguirre, JE, Alexander, P, Ali, ZS, Balfour, Y, Beardsley, AP, Bernardi, G, Billings, TS, Bowman, JD, Bradley, RF, Bull, P, Burba, J, Carilli, CL, Cheng, C, Dexter, M, Dillon, JS, Ewall-Wice, A, Fritz, R, Furlanetto, SR, Gale-Sides, K, Glendenning, B, Gorthi, D, Greig, B, Grobbelaar, J, Halday, Z, Hazelton, BJ, Hewitt, JN, Hickish, J, Jacobs, DC, Josaitis, A, Julius, A, Kern, NS, Kerrigan, J, Kim, H, Kittiwisit, P, Kohn, SA, Kolopanis, M, Lanman, A, Plante, PL, Lekalake, T, Liu, A, Macmahon, D, Malan, L, Malgas, C, Maree, M, Martinot, ZE, Matsetela, E, Mena Parra, J, Mesinger, A, Molewa, M, Morales, MF, Mosiane, T, Neben, AR, Nikolic, B, Parsons, AR, Patra, N, Pieterse, S, Pober, JC, Razavi-Ghods, N, Robnett, J, Rosie, K, Sims, P, Smith, C, Syce, A, Thyagarajan, N, Williams, PKG, and Zheng, H
Subjects: instrumentation: interferometers, methods: numerical, techniques: interferometric, telescopes, dark ages, reionization, first stars, astro-ph.IM, dark ages, reionization, Astronomy & Astrophysics, Astronomical and Space Sciences
Abstract: The detection of the Epoch of Reionization (EoR) delay power spectrum using a 'foreground avoidance method' highly depends on the instrument chromaticity. The systematic effects induced by the radio telescope spread the foreground signal in the delay domain, which contaminates the EoR window theoretically observable. Applied to the Hydrogen Epoch of Reionization Array (HERA), this paper combines detailed electromagnetic and electrical simulations in order to model the chromatic effects of the instrument, and quantify its frequency and time responses. In particular, the effects of the analogue receiver, transmission cables, and mutual coupling are included. These simulations are able to accurately predict the intensity of the reflections occurring in the 150-m cable which links the antenna to the backend. They also show that electromagnetic waves can propagate from one dish to another one through large sections of the array due to mutual coupling. The simulated system time response is attenuated by a factor 104 after a characteristic delay which depends on the size of the array and on the antenna position. Ultimately, the system response is attenuated by a factor 105 after 1400 ns because of the reflections in the cable, which corresponds to characterizable ka-modes above 0.7 $h\,\,\rm {Mpc}^{-1}$ at 150 MHz. Thus, this new study shows that the detection of the EoR signal with HERA Phase I will be more challenging than expected. On the other hand, it improves our understanding of the telescope, which is essential to mitigate the instrument chromaticity.
Published: 2021

91. Absolute Calibration Strategies for the Hydrogen Epoch of Reionization Array and Their Impact on the 21 cm Power Spectrum

Author: Kern, Nicholas S., Dillon, Joshua S., Parsons, Aaron R., Carilli, Christopher L., Bernardi, Gianni, Abdurashidova, Zara, Aguirre, James E., Alexander, Paul, Ali, Zaki S., Balfour, Yanga, Beardsley, Adam P., Billings, Tashalee S., Bowman, Judd D., Bradley, Richard F., Bull, Philip, Burba, Jacob, Carey, Steven, Cheng, Carina, DeBoer, David R., Dexter, Matt, Acedo, Eloy de Lera, Ely, John, Ewall-Wice, Aaron, Fagnoni, Nicolas, Fritz, Randall, Furlanetto, Steve R., Gale-Sides, Kingsley, Glendenning, Brian, Gorthi, Deepthi, Greig, Bradley, Grobbelaar, Jasper, Halday, Ziyaad, Hazelton, Bryna J., Hewitt, Jacqueline N., Hickish, Jack, Jacobs, Daniel C., Julius, Austin, Kerrigan, Joshua, Kittiwisit, Piyanat, Kohn, Saul A., Kolopanis, Matthew, Lanman, Adam, La Plante, Paul, Lekalake, Telalo, Liu, Adrian, MacMahon, David, Malan, Lourence, Malgas, Cresshim, Maree, Matthys, Martinot, Zachary E., Matsetela, Eunice, Mesinger, Andrei, Molewa, Mathakane, Morales, Miguel F., Mosiane, Tshegofalang, Murray, Steven G., Neben, Abraham R., Nikolic, Bojan, Nunhokee, Chuneeta D., Patra, Nipanjana, Pieterse, Samantha, Pober, Jonathan C., Razavi-Ghods, Nima, Ringuette, Jon, Robnett, James, Rosie, Kathryn, Sims, Peter, Smith, Craig, Syce, Angelo, Thyagarajan, Nithyanandan, Williams, Peter K. G., and Zheng, Haoxuan
Subjects: Astrophysics - Instrumentation and Methods for Astrophysics, Astrophysics - Cosmology and Nongalactic Astrophysics
Abstract: We discuss absolute calibration strategies for Phase I of the Hydrogen Epoch of Reionization Array (HERA), which aims to measure the cosmological 21 cm signal from the Epoch of Reionization (EoR). HERA is a drift-scan array with a 10 degree wide field of view, meaning bright, well-characterized point source transits are scarce. This, combined with HERA's redundant sampling of the uv plane and the modest angular resolution of the Phase I instrument, make traditional sky-based and self-calibration techniques difficult to implement with high dynamic range. Nonetheless, in this work we demonstrate calibration for HERA using point source catalogues and electromagnetic simulations of its primary beam. We show that unmodeled diffuse flux and instrumental contaminants can corrupt the gain solutions, and present a gain smoothing approach for mitigating their impact on the 21 cm power spectrum. We also demonstrate a hybrid sky and redundant calibration scheme and compare it to pure sky-based calibration, showing only a marginal improvement to the gain solutions at intermediate delay scales. Our work suggests that the HERA Phase I system can be well-calibrated for a foreground-avoidance power spectrum estimator by applying direction-independent gains with a small set of degrees of freedom across the frequency and time axes., Comment: Accepted to ApJ
Published: 2019
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92. The Control Unit of the KM3NeT Data Acquisition System

Author: Aiello, S., Ameli, F., Andre, M., Androulakis, G., Anghinolfi, M., Anton, G., Ardid, M., Aublin, J., Bagatelas, C., Barbarino, G., Baret, B., Pree, S. Basegmez du, Bendahman, M., Berbee, E., Berg, A. M. van den, Bertin, V., Biagi, S., Biagioni, A., Bissinger, M., Boumaaza, J., Bourret, S., Bouta, M., Bouvet, G., Bouwhuis, M., Bozza, C., Branzas, H., Bruchner, M., Bruijn, R., Brunner, J., Buis, E., Buompane, R., Busto, J., Calvo, D., Capone, A., Celli, S., Chabab, M., Chau, N., Cherubini, S., Chiarella, V., Chiarusi, T., Circella, M., Cocimano, R., Coelho, J. A. B., Coleiro, A., Molla, M. Colomer, Coniglione, R., Coyle, P., Creusot, A., Cuttone, G., D'Onofrio, A., Dallier, R., De Palma, M., Di Palma, I., Díaz, A. F., Diego-Tortosa, D., Distefano, C., Domi, A., Donà, R., Donzaud, C., Dornic, D., Dörr, M., Durocher, M., Eberl, T., Bojaddaini, I. El, Eljarrari, H., Elsaesser, D., Enzenhöfer, A., Fermani, P., Ferrara, G., Filipovic, M. D., Franco, A., Fusco, L. A., Gal, T., Soto, A. Garcia, Garufi, F., Gialanella, L., Giorgio, E., Gozzini, S. R., Gracia, R., Graf, K., Grasso, D., Grégoire, T., Grella, G., Guderian, D., Guidi, C., Hallmann, S., Hamdaoui, H., van Haren, H., Heijboer, A., Hekalo, A., Hernández-Rey, J. J., Hofestädt, J., Huang, F., Illuminati, G., James, C. W., de Jong, M., de Jong, P., Kadler, M., Kalaczynski, P., Kalekin, O., Katz, U. F., Chowdhury, N. R. Khan, van der Knaap, F., Koffeman, E. N., Kooijman, P., Kouchner, A., Kulikovskiy, V., Lahmann, R., Larosa, G., Breton, R. Le, Leone, F., Leonora, E., Levi, G., Lincetto, M., Lonardo, A., Longhitano, F., Lopez-Coto, D., Maggi, G., Manczak, J., Mannheim, K., Margiotta, A., Marinelli, A., Markou, C., Martignac, G., Martin, L., Martínez-Mora, J. A., Martini, A., Marzaioli, F., Mazzou, S., Mele, R., Melis, K. W., Migliozzi, P., Migneco, E., Mijakowski, P., Miranda, L. S., Mollo, C. M., Morganti, M., Moser, M., Moussa, A., Muller, R., Musumeci, M., Nauta, L., Navas, S., Nicolau, C. A., Nielsen, C., Fearraigh, B. O', Organokov, M., Orlando, A., Panagopoulos, V., Papalashvili, G., Papaleo, R., Pastore, C., Pavalas, G. E., Pellegrino, C., Perrin-Terrin, M., Piattelli, P., Pieterse, C., Pikounis, K., Pisanti, O., Poirè, C., Polydefki, G., Popa, V., Post, M., Pradier, T., Puhlhofer, G., Pulvirenti, S., Quinn, L., Raffaelli, F., Randazzo, N., Rapicavoli, A., Razzaque, S., Real, D., Reck, S., Reubelt, J., Riccobene, G., Richer, M., Rigalleau, L., Rovelli, A., Salvadori, I., Samtleben, D. F. E., Losa, A. Sánchez, Sanguineti, M., Santangelo, A., Santonocito, D., Sapienza, P., Schnabel, J., Sciacca, V., Seneca, J., Sgura, I., Shanidze, R., Sharma, A., Simeone, F., Sinopoulou, A., Spisso, B., Spurio, M., Stavropoulos, D., Steijger, J., Stellacci, S. M., Strandberg, B., Stransky, D., Taiuti, M., Tayalati, Y., Tenllado, E., Thakore, T., Tingay, S., Tzamariudaki, E., Tzanetatos, D., Van Elewyck, V., Vannoye, G., Versari, F., Viola, S., Vivolo, D., de Wasseige, G., Wilms, J., Wojaczynski, R., de Wolf, E., Zaborov, D., Zegarelli, A., Zornoza, J. D., and Zúñiga, J.
Subjects: Astrophysics - Instrumentation and Methods for Astrophysics, High Energy Physics - Experiment
Abstract: The KM3NeT Collaboration runs a multi-site neutrino observatory in the Mediterranean Sea. Water Cherenkov particle detectors, deep in the sea and far off the coasts of France and Italy, are already taking data while incremental construction progresses. Data Acquisition Control software is operating off-shore detectors as well as testing and qualification stations for their components. The software, named Control Unit, is highly modular. It can undergo upgrades and reconfiguration with the acquisition running. Interplay with the central database of the Collaboration is obtained in a way that allows for data taking even if Internet links fail. In order to simplify the management of computing resources in the long term, and to cope with possible hardware failures of one or more computers, the KM3NeT Control Unit software features a custom dynamic resource provisioning and failover technology, which is especially important for ensuring continuity in case of rare transient events in multi-messenger astronomy. The software architecture relies on ubiquitous tools and broadly adopted technologies and has been successfully tested on several operating systems.
Published: 2019
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93. Mitigating Internal Instrument Coupling II: A Method Demonstration with the Hydrogen Epoch of Reionization Array

Author: Kern, Nicholas S., Parsons, Aaron R., Dillon, Joshua S., Lanman, Adam E., Liu, Adrian, Bull, Philip, Ewall-Wice, Aaron, Abdurashidova, Zara, Aguirre, James E., Alexander, Paul, Ali, Zaki S., Balfour, Yanga, Beardsley, Adam P., Bernardi, Gianni, Bowman, Judd D., Bradley, Richard F., Burba, Jacob, Carilli, Chris L., Cheng, Carina, DeBoer, David R., Dexter, Matt, Acedo, Eloy de Lera, Fagnoni, Nicolas, Fritz, Randall, Furlanetto, Steve R., Glendenning, Brian, Gorthi, Deepthi, Greig, Bradley, Grobbelaar, Jasper, Halday, Ziyaad, Hazelton, Bryna J., Hewitt, Jacqueline N., Hickish, Jack, Jacobs, Daniel C., Julius, Austin, Kerrigan, Joshua, Kittiwisit, Piyanat, Kohn, Saul A., Kolopanis, Matthew, La Plante, Paul, Lekalake, Telalo, MacMahon, David, Malan, Lourence, Malgas, Cresshim, Maree, Matthys, Martinot, Zachary E., Matsetela, Eunice, Mesinger, Andrei, Molewa, Mathakane, Morales, Miguel F., Mosiane, Tshegofalang, Murray, Steven G., Neben, Abraham R., Patra, Nipanjana, Pieterse, Samantha, Pober, Jonathan C., Razavi-Ghods, Nima, Ringuette, Jon, Robnett, James, Rosie, Kathryn, Sims, Peter, Smith, Craig, Syce, Angelo, Thyagarajan, Nithyanandan, Williams, Peter K. G., and Zheng, Haoxuan
Subjects: Astrophysics - Instrumentation and Methods for Astrophysics, Astrophysics - Cosmology and Nongalactic Astrophysics
Abstract: We present a study of internal reflection and cross coupling systematics in Phase I of the Hydrogen Epoch of Reionization Array (HERA). In a companion paper, we outlined the mathematical formalism for such systematics and presented algorithms for modeling and removing them from the data. In this work, we apply these techniques to data from HERA's first observing season as a method demonstration. The data show evidence for systematics that, without removal, would hinder a detection of the 21 cm power spectrum for the targeted EoR line-of-sight modes in the range 0.2 < k_parallel < 0.5\ h^-1 Mpc. After systematic removal, we find we can recover these modes in the power spectrum down to the integrated noise-floor of a nightly observation, achieving a dynamic range in the EoR window of 10^-6 in power (mK^2 units) with respect to the bright galactic foreground signal. In the absence of other systematics and assuming the systematic suppression demonstrated here continues to lower noise levels, our results suggest that fully-integrated HERA Phase I may have the capacity to set competitive upper limits on the 21 cm power spectrum. For future observing seasons, HERA will have upgraded analog and digital hardware to better control these systematics in the field., Comment: Submitted to ApJ
Published: 2019
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94. Understanding the HERA Phase I receiver system with simulations and its impact on the detectability of the EoR delay power spectrum

Author: Fagnoni, Nicolas, Acedo, Eloy de Lera, DeBoer, David R., Abdurashidova, Zara, Aguirre, James E., Alexander, Paul, Ali, Zaki S., Balfour, Yanga, Beardsley, Adam P., Bernardi, Gianni, Billings, Tashalee S., Bowman, Judd D., Bradley, Richard F., Bull, Phil, Burba, Jacob, Carilli, Chris L., Cheng, Carina, Dexter, Matt, Dillon, Joshua S., Ewall-Wice, Aaron, Fritz, Randall, Furlanetto, Steve R., Gale-Sides, Kingsley, Glendenning, Brian, Gorthi, Deepthi, Greig, Bradley, Grobbelaar, Jasper, Halday, Ziyaad, Hazelton, Bryna J., Hewitt, Jacqueline N., Hickish, Jack, Jacobs, Daniel C., Josaitis, Alec, Julius, Austin, Kern, Nicholas S., Kerrigan, Joshua, Kim, Honggeun, Kittiwisit, Piyanat, Kohn, Saul A., Kolopanis, Matthew, Lanman, Adam, La Plante, Paul, Lekalake, Telalo, Liu, Adrian, MacMahon, David, Malan, Lourence, Malgas, Cresshim, Maree, Matthys, Martinot, Zachary E., Matsetela, Eunice, Parra, Juan Mena, Mesinger, Andrei, Molewa, Mathakane, Morales, Miguel F., Mosiane, Tshegofalang, Neben, Abraham R., Nikolic, Bojan, Parsons, Aaron R., Patra, Nipanjana, Pieterse, Samantha, Pober, Jonathan C., Razavi-Ghods, Nima, Robnett, James, Rosie, Kathryn, Sims, Peter, Smith, Craig, Syce, Angelo, Thyagarajan, Nithyanandan, Williams, Peter K. G., and Zheng, Haoxuan
Subjects: Astrophysics - Instrumentation and Methods for Astrophysics
Abstract: The detection of the Epoch of Reionization (EoR) delay power spectrum using a "foreground avoidance method" highly depends on the instrument chromaticity. The systematic effects induced by the radio-telescope spread the foreground signal in the delay domain, which contaminates the EoR window theoretically observable. Applied to the Hydrogen Epoch of Reionization Array (HERA), this paper combines detailed electromagnetic and electrical simulations in order to model the chromatic effects of the instrument, and quantify its frequency and time responses. In particular, the effects of the analogue receiver, transmission cables, and mutual coupling are included. These simulations are able to accurately predict the intensity of the reflections occurring in the 150-m cable which links the antenna to the back-end. They also show that electromagnetic waves can propagate from one dish to another one through large sections of the array due to mutual coupling. The simulated system time response is attenuated by a factor $10^{4}$ after a characteristic delay which depends on the size of the array and on the antenna position. Ultimately, the system response is attenuated by a factor $10^{5}$ after 1400 ns because of the reflections in the cable, which corresponds to characterizable ${k_\parallel}$-modes above 0.7 $h\;\rm{Mpc}^{-1}$ at 150 MHz. Thus, this new study shows that the detection of the EoR signal with HERA Phase I will be more challenging than expected. On the other hand, it improves our understanding of the telescope, which is essential to mitigate the instrument chromaticity., Comment: 13 pages, 17 figures - Submitted to MNRAS - 2nd revision
Published: 2019
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95. Elimination Distances, Blocking Sets, and Kernels for Vertex Cover

Author: Hols, Eva-Maria C., Kratsch, Stefan, and Pieterse, Astrid
Subjects: Computer Science - Computational Complexity, Computer Science - Data Structures and Algorithms
Abstract: The Vertex Cover problem plays an essential role in the study of polynomial kernelization in parameterized complexity, i.e., the study of provable and efficient preprocessing for NP-hard problems. Motivated by the great variety of positive and negative results for kernelization for Vertex Cover subject to different parameters and graph classes, we seek to unify and generalize them using so-called blocking sets, which have played implicit and explicit roles in many results. We show that in the most-studied setting, parameterized by the size of a deletion set to a specified graph class $\mathcal{C}$, bounded minimal blocking set size is necessary but not sufficient to get a polynomial kernelization. Under mild technical assumptions, bounded minimal blocking set size is showed to allow an essentially tight efficient reduction in the number of connected components. We then determine the exact maximum size of minimal blocking sets for graphs of bounded elimination distance to any hereditary class $\mathcal{C}$, including the case of graphs of bounded treedepth. We get similar but not tight bounds for certain non-hereditary classes $\mathcal{C}$, including the class $\mathcal{C}_{LP}$ of graphs where integral and fractional vertex cover size coincide. These bounds allow us to derive polynomial kernels for Vertex Cover parameterized by the size of a deletion set to graphs of bounded elimination distance to, e.g., forest, bipartite, or $\mathcal{C}_{LP}$ graphs.
Published: 2019

96. Parameterized Complexity of Conflict-free Graph Coloring

Author: Bodlaender, Hans L., Kolay, Sudeshna, and Pieterse, Astrid
Subjects: Computer Science - Computational Complexity, Computer Science - Data Structures and Algorithms
Abstract: Given a graph G, a q-open neighborhood conflict-free coloring or q-ONCF-coloring is a vertex coloring $c:V(G) \rightarrow \{1,2,\ldots,q\}$ such that for each vertex $v \in V(G)$ there is a vertex in $N(v)$ that is uniquely colored from the rest of the vertices in $N(v)$. When we replace $N(v)$ by the closed neighborhood $N[v]$, then we call such a coloring a q-closed neighborhood conflict-free coloring or simply q-CNCF-coloring. In this paper, we study the NP-hard decision questions of whether for a constant q an input graph has a q-ONCF-coloring or a q-CNCF-coloring. We will study these two problems in the parameterized setting. First of all, we study running time bounds on FPT-algorithms for these problems, when parameterized by treewidth. We improve the existing upper bounds, and also provide lower bounds on the running time under ETH and SETH. Secondly, we study the kernelization complexity of both problems, using vertex cover as the parameter. We show that both $(q \geq 2)$-ONCF-coloring and $(q \geq 3)$-CNCF-coloring cannot have polynomial kernels when parameterized by the size of a vertex cover unless $NP \in coNP/poly$. However, we obtain a polynomial kernel for 2-CNCF-coloring parameterized by vertex cover. We conclude with some combinatorial results. Denote $\chi_{ON}(G)$ and $\chi_{CN}(G)$ to be the minimum number of colors required to ONCF-color and CNCF-color G, respectively. Upper bounds on $\chi_{CN}(G)$ with respect to structural parameters like minimum vertex cover size, minimum feedback vertex set size and treewidth are known. To the best of our knowledge only an upper bound on $\chi_{ON}(G)$ with respect to minimum vertex cover size was known. We provide tight bounds for $\chi_{ON}(G)$ with respect to minimum vertex cover size. Also, we provide the first upper bounds on $\chi_{ON}(G)$ with respect to minimum feedback vertex set size and treewidth., Comment: Accepted to WADS 2019
Published: 2019

97. Unsalaried health workers in Sierra Leone: a scoping review of the literature to establish their impact on healthcare delivery

Author: Pieterse, Pieternella and Saracini, Federico
Published: 2023
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98. Radiographic and histological evaluation of bone formation induced by rhBMP-2-incorporated biomimetic calcium phosphate material in clinical alveolar sockets preservation

Author: Sun, Yuanyuan, Xu, Chunfeng, Wang, Mingjie, Wei, Lingfei, Pieterse, Herman, Wu, Yiqun, and Liu, Yuelian
Published: 2023
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99. Correction: The effectiveness of immediate versus delayed tubal flushing with oil-based contrast in women with unexplained infertility (H2Oil-timing study): study protocol of a randomized controlled trial

Author: Kamphuis, D., Rosielle, K., van Welie, N., Roest, I., van Dongen, A. J. C. M., Brinkhuis, E. A., Bourdrez, P., Mozes, A., Verhoeve, H. R., van der Ham, D. P., Vrouenraets, F. P. J. M., Risseeuw, J. J., van de Laar, T., Janse, F., Hartog, J. E. den, de Hundt, M., Hooker, A. B., Huppelschoten, A. G., Pieterse, Q. D., Bongers, M. Y., Stoker, J., Koks, C. A. M., Lambalk, C. B., Hemingway, A., Li, W., Mol, B. W. J., Dreyer, K., and Mijatovic, V.
Published: 2023
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100. Genes associated with cognitive ability and HAR show overlapping expression patterns in human cortical neuron types

Author: Driessens, Stan L. W., Galakhova, Anna A., Heyer, Djai B., Pieterse, Isabel J., Wilbers, René, Mertens, Eline J., Waleboer, Femke, Heistek, Tim S., Coenen, Loet, Meijer, Julia R., Idema, Sander, de Witt Hamer, Philip C., Noske, David P., de Kock, Christiaan P. J., Lee, Brian R., Smith, Kimberly, Ting, Jonathan T., Lein, Ed S., Mansvelder, Huibert D., and Goriounova, Natalia A.
Published: 2023
Full Text: View/download PDF

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