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Your search keyword '"Zuccarello, Francesca"' showing total 18 results
Start Over Author "Zuccarello, Francesca" Publication Type Reports
18 results on '"Zuccarello, Francesca"'

1. Quantifying Properties of Photospheric Magnetic Cancellations in the Quiet Sun Internetwork

Author

Ledvina, Vincent E., Kazachenko, Maria D., Criscuoli, Serena, Tilipman, Dennis, Ermolli, Ilaria, Falco, Mariachiara, Guglielmino, Salvatore, Jafarzadeh, Shahin, van der Voort, Luc Rouppe, and Zuccarello, Francesca

Subjects
Astrophysics - Solar and Stellar Astrophysics
Abstract

We analyzed spectropolarimetric data from the Swedish 1-meter Solar Telescope to investigate physical properties of small-scale magnetic cancellations in the quiet Sun photosphere. Specifically, we looked at the full Stokes polarization profiles along the Fe I 557.6 nm and of the Fe I 630.1 nm lines measured by CRisp Imaging SpectroPolarimeter (CRISP) to study temporal evolution of the line-of-sight (LOS) magnetic field during 42.5 minutes of quiet Sun evolution. From this magnetogram sequence, we visually identified 38 cancellation events. We then used Yet Another Feature Tracking Algorithm (YAFTA) to characterize physical properties of these magnetic cancellations. We found on average $1.6\times10^{16}$ Mx of magnetic flux cancelled in each event with an average cancellation rate of $3.8\times10^{14}$ Mx s$^{-1}$. The derived cancelled flux is associated with strong downflows, with an average speed of $V_\mathrm{LOS}\approx1.1$ km s$^{-1}$. Our results show that the average lifetime of each event is $9.2$ minutes with an average $44.8\%$ of initial magnetic flux being cancelled. Our estimates of magnetic fluxes provide a lower limit since studied magnetic cancellation events have magnetic field values that are very close to the instrument noise level. We observed no horizontal magnetic fields at the cancellation sites and therefore can not conclude whether the events are associated structures that could cause magnetic reconnection., Comment: 19 pages, 18 figures, 2 tables, accepted into ApJ on 06/08/2022

Published
2022
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2. On the evolution of a sub-C class flare: a showcase for the capabilities of the revamped Catania Solar Telescope

Author

Romano, Paolo, Guglielmino, Salvo L., Costa, Pierfrancesco, Falco, Mariachiara, Buttaccio, Salvatore, Costa, Alessandro, Martinetti, Eugenio, Occhipinti, Giovanni, Spadaro, Daniele, Ventura, Rita, Capuano, Giuseppe E., and Zuccarello, Francesca

Subjects
Astrophysics - Solar and Stellar Astrophysics, Astrophysics - Instrumentation and Methods for Astrophysics
Abstract

Solar flares are occasionally responsible for severe Space Weather events, which can affect space-borne and ground-based infrastructures, endangering anthropic technological activities and even human health and safety. Thus, an essential activity in the framework of Space Weather monitoring is devoted to the observation of the activity level of the Sun. In this context, the acquisition system of the Catania Solar Telescope has been recently upgraded in order to improve its contribution to the European Space Agency (ESA) - Space Weather Service Network through the ESA Portal, which represents the main asset for Space Weather in Europe. Here, we describe the hardware and software upgrades of the Catania Solar Telescope and the main data products provided by this facility, which include full-disc images of the photosphere and chromosphere, together with a detailed characterization of the sunspot groups. As a showcase of the observational capabilities of the revamped Catania Solar Telescope, we report the analysis of a B5.4 class flare occurred on 2020 December 7, simultaneously observed by the IRIS and SDO satellites.

Published
2021
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3. Comparative case study of two methods to assess the eruptive potential of selected active regions

Author

Zuccarello, Francesca, Ermolli, Ilaria, Korsos, Marianna B., Giorgi, Fabrizio, Guglielmino, Salvo L., Erdelyi, Robertus, and Romano, Paolo

Subjects
Astrophysics - Solar and Stellar Astrophysics
Abstract

Solar eruptive events, like flares and coronal mass ejections, are characterized by the rapid release of energy that can give rise to emission of radiation across the entire electromagnetic spectrum and to an abrupt significant increase in the kinetic energy of particles. These energetic phenomena can have important effects on the Space Weather conditions and therefore it is necessary to understand their origin, in particular, what is the eruptive potential of an active region (AR). In these case studies, we compare two distinct methods that were used in previous works to investigate the variations of some characteristic physical parameters during the pre-flare states of flaring ARs. These methods consider: i) the magnetic flux evolution and the magnetic helicity accumulation, and ii) the fractal and multi-fractal properties of flux concentrations in ARs. Our comparative analysis is based on time series of photospheric data obtained by the Solar Dynamics Observatory between March 2011 and June 2013. We selected two distinct samples of ARs: one is distinguished by the occurrence of more energetic M- and X-class flare events, that may have a rapid effect on not just the near-Earth space, but also on the terrestrial environment; the second is characterized by no-flares or having just few C- and B-class flares. We found that the two tested methods complement each other in their ability to assess the eruptive potentials of ARs and could be employed to identify ARs prone to flaring activity. Based on the presented case study, we suggest that using a combination of different methods may aid to identify more reliably the eruptive potentials of ARs and help to better understand the pre-flare states.

Published
2021
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4. Continuum enhancements, line profiles and magnetic field evolution during consecutive flares

Author

Zuccarello, Francesca, Guglielmino, Salvo L., Capparelli, Vincenzo, Mathioudakis, Mihalis, Keys, Peter H., Criscuoli, Serena, Falco, Mariachiara, and Murabito, Mariarita

Subjects
Astrophysics - Solar and Stellar Astrophysics, Physics - Space Physics
Abstract

During solar flares, magnetic energy can be converted into electromagnetic radiation from radio waves to $\gamma$ rays. Enhancements in the continuum at visible wavelengths give rise to white-light flares, as well as continuum enhancements in the FUV and NUV passbands. In addition, the strong energy release in these events can lead to the rearrangement of the magnetic field at the photospheric level, causing morphological changes in large and stable magnetic structures like sunspots. In this context, we describe observations acquired by satellite instruments (IRIS, SDO/HMI, Hinode/SOT) and ground-based telescopes (ROSA/DST) during two consecutive C7.0 and X1.6 flares occurred in active region NOAA 12205 on 2014 November 7. The flare was accompanied by an eruption. The results of the analysis show the presence of continuum enhancements during the evolution of the events, observed both in ROSA images and in \textit{IRIS} spectra. In the latter, a prominent blue-shifted component is observed at the onset of the eruption. We investigate the role played by the evolution of the $\delta$ sunspots of the active region in the flare triggering, and finally we discuss the changes in the penumbrae surrounding these sunspots as a further consequence of these flares., Comment: 19 pages, accepted for ApJ; some figures are in B/W to accomplish size limits

Published
2019
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5. IRIS observations of magnetic interactions in the solar atmosphere between pre-existing and emerging magnetic fields. II. UV emission properties

Author

Guglielmino, Salvo L., Young, Peter R., and Zuccarello, Francesca

Subjects
Astrophysics - Solar and Stellar Astrophysics
Abstract

Multi-wavelength ultraviolet (UV) observations by the IRIS satellite in active region NOAA 12529 have recently pointed out the presence of long-lasting brightenings, akin to UV bursts, and simultaneous plasma ejections occurring in the upper chromosphere and transition region during secondary flux emergence. These signatures have been interpreted as evidence of small-scale, recurrent magnetic reconnection episodes between the emerging flux region (EFR) and the pre-existing plage field. Here, we characterize the UV emission of these strong, intermittent brightenings and we study the surge activity above the chromospheric arch filament system (AFS) overlying the EFR. We analyze the surges and the cospatial brightenings observed at different wavelengths. We find an asymmetry in the emission between the blue and red wings of the Si IV 1402 \AA{} and Mg II k 2796.3 \AA{} lines, which clearly outlines the dynamics of the structures above the AFS that form during the small-scale eruptive phenomena. We also detect a correlation between the Doppler velocity and skewness of the Si IV 1394 \AA{} and 1402 \AA{} line profiles in the UV burst pixels. Finally, we show that genuine emission in the Fe XII 1349.4 \AA{} line is cospatial to the Si IV brightenings. This definitely reveals a pure coronal counterpart to the reconnection event., Comment: 19 pages, 8 figures + 3 figures in the Appendix; accepted in ApJ

Published
2018
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6. IRIS observations of magnetic interactions in the solar atmosphere between pre-existing and emerging magnetic fields. I. Overall evolution

Author

Guglielmino, Salvo L., Zuccarello, Francesca, Young, Peter R., Murabito, Mariariata, and Romano, Paolo

Subjects
Astrophysics - Solar and Stellar Astrophysics
Abstract

We report multi-wavelength ultraviolet observations taken with the IRIS satellite, concerning the emergence phase in the upper chromosphere and transition region of an emerging flux region (EFR) embedded in the pre-existing field of active region NOAA 12529. IRIS data are complemented by full-disk observations of the Solar Dynamics Observatory satellite, relevant to the photosphere and the corona. The photospheric configuration of the EFR is also analyzed by measurements taken with the spectropolarimeter aboard the Hinode satellite, when the EFR was fully developed. Recurrent intense brightenings that resemble UV bursts, with counterparts in all coronal passbands, are identified at the edges of the EFR. Jet activity is also observed at chromospheric and coronal levels, near the observed brightenings. The analysis of the IRIS line profiles reveals the heating of dense plasma in the low solar atmosphere and the driving of bi-directional high-velocity flows with speed up to 100 km/s at the same locations. Compared with previous observations and numerical models, these signatures suggest evidence of several long-lasting, small-scale magnetic reconnection episodes between the emerging bipole and the ambient field. This process leads to the cancellation of a pre-existing photospheric flux concentration and appears to occur higher in the atmosphere than usually found in UV bursts, explaining the observed coronal counterparts., Comment: 12 figures, accepted in ApJ

Published
2018
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7. H${\alpha}$ and H${\beta}$ emission in a C3.3 solar flare: comparison between observations and simulations

Author

Capparelli, Vincenzo, Zuccarello, Francesca, Romano, Paolo, Simoes, Paulo J. A., Fletcher, Lyndsay, Kuridze, David, Mathioudakis, Mihalis, Keys, Peter H., Cauzzi, Gianna, and Carlsson, Mats

Subjects
Astrophysics - Solar and Stellar Astrophysics
Abstract

The Hydrogen Balmer series is a basic radiative loss channel from the flaring solar chromosphere. We report here on the analysis of an extremely rare set of simultaneous observations of a solar flare in the H${\alpha}$ and H${\beta}$ lines at high spatial and temporal resolution, which were acquired at the Dunn Solar Telescope. Images of the C3.3 flare (SOL2014-04-22T15:22) made at various wavelengths along the H${\alpha}$ line profile by the Interferometric Bidimensional Spectrometer (IBIS) and in the H${\beta}$ with the Rapid Oscillations in the Solar Atmosphere (ROSA) broadband imager are analyzed to obtain the intensity evolution. The H${\alpha}$ and H${\beta}$ intensity excesses in three identified flare footpoints are well correlated in time. We examine the ratio of H${\alpha}$ to H${\beta}$ flare excess, which was proposed by previous authors as a possible diagnostic of the level of electron beam energy input. In the stronger footpoints, the typical value of the the H${\alpha}$/H${\beta}$ intensity ratio observed is $\sim 0.4-0.5$, in broad agreement with values obtained from a RADYN non-LTE simulation driven by an electron beam with parameters constrained (as far as possible) by observation. The weaker footpoint has a larger H${\alpha}$/H${\beta}$ ratio, again consistent with a RADYN simulation but with a smaller energy flux. The H${\alpha}$ line profiles observed have a less prominent central reversal than is predicted by the RADYN results, but can be brought into agreement if the H${\alpha}$-emitting material has a filling factor of around 0.2--0.3., Comment: 14 pages, 17 figures

Published
2017
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8. Observational Evidence of a Flux Rope within a Sunspot Umbra

Author

Guglielmino, Salvo L., Romano, Paolo, and Zuccarello, Francesca

Subjects
Astrophysics - Solar and Stellar Astrophysics
Abstract

We observed an elongated filamentary bright structure inside the umbra of the big sunspot in active region NOAA 12529, which differs from the light bridges usually observed in sunspots for its morphology, magnetic configuration, and velocity field. We used observations taken with the Solar Dynamic Observatory satellite to characterize this feature. Its lifetime is 5 days, during which it reaches a maximum length of about 30". In the maps of the vertical component of the photospheric magnetic field, a portion of the feature has a polarity opposite to that of the hosting sunspot. At the same time, in the entire feature the horizontal component of the magnetic field is about 2000 G, substantially stronger than in the surrounding penumbral filaments. Doppler velocity maps reveal the presence of both upward and downward plasma motions along the structure at the photospheric level. Moreover, looking at the chromospheric level, we noted that it is located in a region corresponding to the edge of a small filament which seems rooted in the sunspot umbra. Therefore, we interpreted the bright structure as the photospheric counterpart of a flux rope touching the sunspot and giving rise to penumbral-like filaments in the umbra., Comment: 6 pages, 3 figures, accepted for ApJL

Published
2017
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9. Polarised kink waves in magnetic elements: evidence for chromospheric helical waves

Author

Stangalini, Marco, Giannattasio, Fabio, Erdélyi, Robertus, Jafarzadeh, Shahin, Consolini, Giuseppe, Criscuoli, Serena, Ermolli, Ilaria, Guglielmino, Salvo Luigi, and Zuccarello, Francesca

Subjects
Astrophysics - Solar and Stellar Astrophysics
Abstract

In recent years, new high spatial resolution observations of the Sun's atmosphere have revealed the presence of a plethora of small-scale magnetic elements down to the resolution limit of current cohort of solar telescopes ($\sim 100-120$ km on the solar photosphere). These small magnetic field concentrations, due to the granular buffeting, can support and guide several magneto-hydrodynamics (MHD) wave modes that would eventually contribute to the energy budget of the upper layers of the atmosphere.\\ In this work, exploiting the high spatial and temporal resolution chromospheric data acquired with the Swedish 1-meter Solar Telescope (SST), and applying the empirical mode decomposition (EMD) technique to the tracking of the solar magnetic features, we analyse the perturbations of the horizontal velocity vector of a set of chromospheric magnetic elements. We find observational evidence that suggests a phase relation between the two components of the velocity vector itself, resulting in its helical motion., Comment: ApJ accepted

Published
2017
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10. The pre-penumbral magnetic canopy in the solar atmosphere

Author

MacTaggart, David, Guglielmino, Salvo, and Zuccarello, Francesca

Subjects
Astrophysics - Solar and Stellar Astrophysics
Abstract

Penumbrae are the manifestation of magnetoconvection in highly inclined (to the vertical direction) magnetic field. The penumbra of a sunspot tends to form, initially, along the arc of the umbra antipodal to the main region of flux emergence. The question of how highly inclined magnetic field can concentrate along the antipodal curves of umbrae, at least initially, remains to be answered. Previous observational studies have suggested the existence of some form of overlying magnetic canopy which acts as the progenitor for penumbrae. We propose that such overlying magnetic canopies are a consequence of how the magnetic field emerges into the atmosphere and are, therefore, part of the emerging region. We show, through simulations of twisted flux tube emergence, that canopies of highly inclined magnetic field form preferentially at the required locations above the photosphere., Comment: Accepted for ApJL

Published
2016
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11. Measurement of the Radiation Energy in the Radio Signal of Extensive Air Showers as a Universal Estimator of Cosmic-Ray Energy

Author

The Pierre Auger Collaboration, Aab, Alexander, Abreu, Pedro, Aglietta, Marco, Ahn, Eun-Joo, Samarai, Imen Al, Albuquerque, Ivone, Allekotte, Ingomar, Allison, Patrick, Almela, Alejandro, Castillo, Jesus Alvarez, Alvarez-Muñiz, Jaime, Batista, Rafael Alves, Ambrosio, Michelangelo, Aminaei, Amin, Anastasi, Gioacchino Alex, Anchordoqui, Luis, Andringa, Sofia, Aramo, Carla, Arqueros, Fernando, Arsene, Nicusor, Asorey, Hernán Gonzalo, Assis, Pedro, Aublin, Julien, Avila, Gualberto, Awal, Nafiun, Badescu, Alina Mihaela, Baus, Colin, Beatty, Jim, Becker, Karl Heinz, Bellido, Jose A., Berat, Corinne, Bertaina, Mario Edoardo, Bertou, Xavier, Biermann, Peter, Billoir, Pierre, Blaess, Simon G., Blanco, Alberto, Blanco, Miguel, Blazek, Jiri, Bleve, Carla, Blümer, Hans, Boháčová, Martina, Boncioli, Denise, Bonifazi, Carla, Borodai, Nataliia, Brack, Jeffrey, Brancus, Iliana, Bretz, Thomas, Bridgeman, Ariel, Brogueira, Pedro, Buchholz, Peter, Bueno, Antonio, Buitink, Stijn, Buscemi, Mario, Caballero-Mora, Karen S., Caccianiga, Barbara, Caccianiga, Lorenzo, Candusso, Marina, Caramete, Laurentiu, Caruso, Rossella, Castellina, Antonella, Cataldi, Gabriella, Cazon, Lorenzo, Cester, Rosanna, Chavez, Alan G., Chiavassa, Andrea, Chinellato, Jose Augusto, Chudoba, Jiri, Cilmo, Marco, Clay, Roger W, Cocciolo, Giuseppe, Colalillo, Roberta, Coleman, Alan, Collica, Laura, Coluccia, Maria Rita, Conceição, Ruben, Contreras, Fernando, Cooper, Mathew J., Cordier, Alain, Coutu, Stephane, Covault, Corbin, Cronin, James, Dallier, Richard, Daniel, Bruno, Dasso, Sergio, Daumiller, Kai, Dawson, Bruce R., de Almeida, Rogerio M., de Jong, Sijbrand J., De Mauro, Giuseppe, Neto, Joao de Mello, De Mitri, Ivan, de Oliveira, Jaime, de Souza, Vitor, del Peral, Luis, Deligny, Olivier, Dhital, Niraj, Di Giulio, Claudio, Di Matteo, Armando, Diaz, Johana Chirinos, Castro, Mary Lucia Díaz, Diogo, Francisco, Dobrigkeit, Carola, Docters, Wendy, D'Olivo, Juan Carlos, Dorofeev, Alexei, Hasankiadeh, Qader Dorosti, Anjos, Rita dos, Dova, Maria Teresa, Ebr, Jan, Engel, Ralph, Erdmann, Martin, Erfani, Mona, Escobar, Carlos O., Espadanal, Joao, Etchegoyen, Alberto, Falcke, Heino, Fang, Ke, Farrar, Glennys, Fauth, Anderson, Fazzini, Norberto, Ferguson, Andrew P., Fick, Brian, Figueira, Juan Manuel, Filevich, Alberto, Filipčič, Andrej, Fratu, Octavian, Freire, Martín Miguel, Fujii, Toshihiro, García, Beatriz, Garcia-Gamez, Diego, Garcia-Pinto, Diego, Gate, Florian, Gemmeke, Hartmut, Gherghel-Lascu, Alexandru, Ghia, Piera Luisa, Giaccari, Ugo, Giammarchi, Marco, Giller, Maria, Głas, Dariusz, Glaser, Christian, Glass, Henry, Golup, Geraldina, Berisso, Mariano Gómez, Vitale, Primo F. Gómez, González, Nicolás, Gookin, Ben, Gordon, Jacob, Gorgi, Alessio, Gorham, Peter, Gouffon, Philippe, Griffith, Nathan, Grillo, Aurelio, Grubb, Trent D., Guarino, Fausto, Guedes, Germano, Hampel, Matías Rolf, Hansen, Patricia, Harari, Diego, Harrison, Thomas A., Hartmann, Sebastian, Harton, John, Haungs, Andreas, Hebbeker, Thomas, Heck, Dieter, Heimann, Philipp, Herve, Alexander E., Hill, Gary C., Hojvat, Carlos, Hollon, Nicholas, Holt, Ewa, Homola, Piotr, Hörandel, Jörg, Horvath, Pavel, Hrabovský, Miroslav, Huber, Daniel, Huege, Tim, Insolia, Antonio, Isar, Paula Gina, Jandt, Ingolf, Jansen, Stefan, Jarne, Cecilia, Johnsen, Jeffrey A., Josebachuili, Mariela, Kääpä, Alex, Kambeitz, Olga, Kampert, Karl Heinz, Kasper, Peter, Katkov, Igor, Keilhauer, Bianca, Kemp, Ernesto, Kieckhafer, Roger, Klages, Hans, Kleifges, Matthias, Kleinfeller, Jonny, Krause, Raphael, Krohm, Nicole, Kuempel, Daniel, Mezek, Gasper Kukec, Kunka, Norbert, Awad, Alaa Metwaly Kuotb, LaHurd, Danielle, Latronico, Luca, Lauer, Robert, Lauscher, Markus, Lautridou, Pascal, Coz, Sandra Le, Lebrun, Didier, Lebrun, Paul, de Oliveira, Marcelo Augusto Leigui, Letessier-Selvon, Antoine, Lhenry-Yvon, Isabelle, Link, Katrin, Lopes, Luis, López, Rebeca, Casado, Aida López, Louedec, Karim, Lucero, Agustin, Malacari, Max, Mallamaci, Manuela, Maller, Jennifer, Mandat, Dusan, Mantsch, Paul, Mariazzi, Analisa, Marin, Vincent, Mariş, Ioana, Marsella, Giovanni, Martello, Daniele, Martinez, Humberto, Bravo, Oscar Martínez, Martraire, Diane, Meza, Jimmy Masías, Mathes, Hermann-Josef, Mathys, Sebastian, Matthews, James, Matthews, John, Matthiae, Giorgio, Maurizio, Daniela, Mayotte, Eric, Mazur, Peter, Medina, Carlos, Medina-Tanco, Gustavo, Meissner, Rebecca, Mello, Victor, Melo, Diego, Menshikov, Alexander, Messina, Stefano, Micheletti, Maria Isabel, Middendorf, Lukas, Minaya, Ignacio A., Miramonti, Lino, Mitrica, Bogdan, Molina-Bueno, Laura, Mollerach, Silvia, Montanet, François, Morello, Carlo, Mostafá, Miguel, Moura, Celio A., Muller, Marcio Aparecido, Müller, Gero, Müller, Sarah, Navas, Sergio, Necesal, Petr, Nellen, Lukas, Nelles, Anna, Neuser, Jens, Nguyen, Phong H., Niculescu-Oglinzanu, Mihai, Niechciol, Marcus, Niemietz, Lukas, Niggemann, Tim, Nitz, Dave, Nosek, Dalibor, Novotny, Vladimir, Nožka, Lyberis, Núñez, Luis, Ochilo, Livingstone, Oikonomou, Foteini, Olinto, Angela, Pacheco, Noelia, Selmi-Dei, Daniel Pakk, Palatka, Miroslav, Pallotta, Juan, Papenbreer, Philipp, Parente, Gonzalo, Parra, Alejandra, Paul, Thomas, Pech, Miroslav, Pękala, Jan, Pelayo, Rodrigo, Pepe, Iuri, Perrone, Lorenzo, Petermann, Emily, Peters, Christine, Petrera, Sergio, Petrov, Yevgeniy, Phuntsok, Jamyang, Piegaia, Ricardo, Pierog, Tanguy, Pieroni, Pablo, Pimenta, Mário, Pirronello, Valerio, Platino, Manuel, Plum, Matthias, Porcelli, Alessio, Porowski, Czeslaw, Prado, Raul Ribeiro, Privitera, Paolo, Prouza, Michael, Quel, Eduardo J, Querchfeld, Sven, Quinn, Sean, Rautenberg, Julian, Ravel, Olivier, Ravignani, Diego, Reinert, Darius, Revenu, Benoît, Ridky, Jan, Risse, Markus, Ristori, Pablo, Rizi, Vincenzo, de Carvalho, Washington Rodrigues, Rojo, Jorge Rubén Rodriguez, Rodríguez-Frías, Maria Dolores, Rogozin, Dmytro, Rosado, Jaime, Roth, Markus, Roulet, Esteban, Rovero, Adrian, Saffi, Steven J., Saftoiu, Alexandra, Salazar, Humberto, Saleh, Ahmed, Greus, Francisco Salesa, Salina, Gaetano, Gomez, Jose Sanabria, Sánchez, Federico, Sanchez-Lucas, Patricia, Santos, Edivaldo Moura, Santos, Eva, Sarazin, Fred, Sarkar, Biswaijt, Sarmento, Raul, Sarmiento-Cano, Christian, Sato, Ricardo, Scarso, Carlos, Schauer, Markus, Scherini, Viviana, Schieler, Harald, Schmidt, David, Scholten, Olaf, Schoorlemmer, Harm, Schovánek, Petr, Schröder, Frank G., Schulz, Alexander, Schulz, Johannes, Schumacher, Johannes, Sciutto, Sergio, Segreto, Alberto, Settimo, Mariangela, Shadkam, Amir, Shellard, Ronald C., Sigl, Guenter, Sima, Octavian, Śmiałkowski, Andrzej, Šmída, Radomir, Snow, Gregory, Sommers, Paul, Sonntag, Sebastian, Sorokin, J., Squartini, Ruben, Srivastava, Yogendra N., Stanca, Denis, Stanič, Samo, Stapleton, James, Stasielak, Jaroslaw, Stephan, Maurice, Stutz, Anne, Suarez, Federico, Durán, Mauricio Suarez, Suomijärvi, Tiina, Supanitsky, A. Daniel, Sutherland, Michael, Swain, John, Szadkowski, Zbigniew, Taborda, Oscar Alejandro, Tapia, Alex, Tepe, Andreas, Theodoro, Vanessa Menezes, Timmermans, Charles, Peixoto, Carlos J. Todero, Toma, Gabriel, Tomankova, Lenka, Tomé, Bernardo, Tonachini, Aurelio, Elipe, Guillermo Torralba, Machado, Diego Torres, Travnicek, Petr, Trini, Marta, Ulrich, Ralf, Unger, Michael, Urban, Martin, Galicia, Jose F. Valdés, Valiño, Ines, Valore, Laura, van Aar, Guus, van Bodegom, Patrick, Berg, Ad M. van den, van Velzen, Sjoert, van Vliet, Arjen, Varela, Enrique, Cárdenas, Bernardo Vargas, Varner, Gary, Vasquez, Rafael, Vázquez, Jose R., Vázquez, Ricardo, Veberič, Darko, Verzi, Valerio, Vicha, Jakub, Videla, Mariela, Villaseñor, Luis, Vlcek, Brian, Vorobiov, Serguei, Wahlberg, Hernan, Wainberg, Oscar, Walz, David, Watson, Alan, Weber, Marc, Weidenhaupt, Klaus, Weindl, Andreas, Welling, Christoph, Werner, Felix, Widom, Allan, Wiencke, Lawrence, Wilczyński, Henryk, Winchen, Tobias, Wittkowski, David, Wundheiler, Brian, Wykes, Sarka, Yang, Lili, Yapici, Tolga, Yushkov, Alexey, Zas, Enrique, Zavrtanik, Danilo, Zavrtanik, Marko, Zepeda, Arnulfo, Zimmermann, Benedikt, Ziolkowski, Michael, and Zuccarello, Francesca

Subjects
Astrophysics - High Energy Astrophysical Phenomena, Astrophysics - Instrumentation and Methods for Astrophysics, High Energy Physics - Experiment
Abstract

We measure the energy emitted by extensive air showers in the form of radio emission in the frequency range from 30 to 80 MHz. Exploiting the accurate energy scale of the Pierre Auger Observatory, we obtain a radiation energy of 15.8 \pm 0.7 (stat) \pm 6.7 (sys) MeV for cosmic rays with an energy of 1 EeV arriving perpendicularly to a geomagnetic field of 0.24 G, scaling quadratically with the cosmic-ray energy. A comparison with predictions from state-of-the-art first-principle calculations shows agreement with our measurement. The radiation energy provides direct access to the calorimetric energy in the electromagnetic cascade of extensive air showers. Comparison with our result thus allows the direct calibration of any cosmic-ray radio detector against the well-established energy scale of the Pierre Auger Observatory., Comment: Replaced with published version. Added journal reference and DOI. Supplemental material in the ancillary files

Published
2016
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12. Energy Estimation of Cosmic Rays with the Engineering Radio Array of the Pierre Auger Observatory

Author

The Pierre Auger Collaboration, Aab, Alexander, Abreu, Pedro, Aglietta, Marco, Ahn, Eun-Joo, Samarai, Imen Al, Albuquerque, Ivone, Allekotte, Ingomar, Allison, Patrick, Almela, Alejandro, Castillo, Jesus Alvarez, Alvarez-Muñiz, Jaime, Batista, Rafael Alves, Ambrosio, Michelangelo, Aminaei, Amin, Anastasi, Gioacchino Alex, Anchordoqui, Luis, Andringa, Sofia, Aramo, Carla, Arqueros, Fernando, Arsene, Nicusor, Asorey, Hernán Gonzalo, Assis, Pedro, Aublin, Julien, Avila, Gualberto, Awal, Nafiun, Badescu, Alina Mihaela, Baus, Colin, Beatty, Jim, Becker, Karl Heinz, Bellido, Jose A., Berat, Corinne, Bertaina, Mario Edoardo, Bertou, Xavier, Biermann, Peter, Billoir, Pierre, Blaess, Simon G., Blanco, Alberto, Blanco, Miguel, Blazek, Jiri, Bleve, Carla, Blümer, Hans, Boháčová, Martina, Boncioli, Denise, Bonifazi, Carla, Borodai, Nataliia, Brack, Jeffrey, Brancus, Iliana, Bretz, Thomas, Bridgeman, Ariel, Brogueira, Pedro, Buchholz, Peter, Bueno, Antonio, Buitink, Stijn, Buscemi, Mario, Caballero-Mora, Karen S., Caccianiga, Barbara, Caccianiga, Lorenzo, Candusso, Marina, Caramete, Laurentiu, Caruso, Rossella, Castellina, Antonella, Cataldi, Gabriella, Cazon, Lorenzo, Cester, Rosanna, Chavez, Alan G., Chiavassa, Andrea, Chinellato, Jose Augusto, Chudoba, Jiri, Cilmo, Marco, Clay, Roger W, Cocciolo, Giuseppe, Colalillo, Roberta, Coleman, Alan, Collica, Laura, Coluccia, Maria Rita, Conceição, Ruben, Contreras, Fernando, Cooper, Mathew J., Cordier, Alain, Coutu, Stephane, Covault, Corbin, Cronin, James, Dallier, Richard, Daniel, Bruno, Dasso, Sergio, Daumiller, Kai, Dawson, Bruce R., de Almeida, Rogerio M., de Jong, Sijbrand J., De Mauro, Giuseppe, Neto, Joao de Mello, De Mitri, Ivan, de Oliveira, Jaime, de Souza, Vitor, del Peral, Luis, Deligny, Olivier, Dhital, Niraj, Di Giulio, Claudio, Di Matteo, Armando, Diaz, Johana Chirinos, Castro, Mary Lucia Díaz, Diogo, Francisco, Dobrigkeit, Carola, Docters, Wendy, D'Olivo, Juan Carlos, Dorofeev, Alexei, Hasankiadeh, Qader Dorosti, Anjos, Rita dos, Dova, Maria Teresa, Ebr, Jan, Engel, Ralph, Erdmann, Martin, Erfani, Mona, Escobar, Carlos O., Espadanal, Joao, Etchegoyen, Alberto, Falcke, Heino, Fang, Ke, Farrar, Glennys, Fauth, Anderson, Fazzini, Norberto, Ferguson, Andrew P., Fick, Brian, Figueira, Juan Manuel, Filevich, Alberto, Filipčič, Andrej, Fratu, Octavian, Freire, Martín Miguel, Fujii, Toshihiro, García, Beatriz, Garcia-Gamez, Diego, Garcia-Pinto, Diego, Gate, Florian, Gemmeke, Hartmut, Gherghel-Lascu, Alexandru, Ghia, Piera Luisa, Giaccari, Ugo, Giammarchi, Marco, Giller, Maria, Głas, Dariusz, Glaser, Christian, Glass, Henry, Golup, Geraldina, Berisso, Mariano Gómez, Vitale, Primo F. Gómez, González, Nicolás, Gookin, Ben, Gordon, Jacob, Gorgi, Alessio, Gorham, Peter, Gouffon, Philippe, Griffith, Nathan, Grillo, Aurelio, Grubb, Trent D., Guarino, Fausto, Guedes, Germano, Hampel, Matías Rolf, Hansen, Patricia, Harari, Diego, Harrison, Thomas A., Hartmann, Sebastian, Harton, John, Haungs, Andreas, Hebbeker, Thomas, Heck, Dieter, Heimann, Philipp, Herve, Alexander E., Hill, Gary C., Hojvat, Carlos, Hollon, Nicholas, Holt, Ewa, Homola, Piotr, Hörandel, Jörg, Horvath, Pavel, Hrabovský, Miroslav, Huber, Daniel, Huege, Tim, Insolia, Antonio, Isar, Paula Gina, Jandt, Ingolf, Jansen, Stefan, Jarne, Cecilia, Johnsen, Jeffrey A., Josebachuili, Mariela, Kääpä, Alex, Kambeitz, Olga, Kampert, Karl Heinz, Kasper, Peter, Katkov, Igor, Keilhauer, Bianca, Kemp, Ernesto, Kieckhafer, Roger, Klages, Hans, Kleifges, Matthias, Kleinfeller, Jonny, Krause, Raphael, Krohm, Nicole, Kuempel, Daniel, Mezek, Gasper Kukec, Kunka, Norbert, Awad, Alaa Metwaly Kuotb, LaHurd, Danielle, Latronico, Luca, Lauer, Robert, Lauscher, Markus, Lautridou, Pascal, Coz, Sandra Le, Lebrun, Didier, Lebrun, Paul, de Oliveira, Marcelo Augusto Leigui, Letessier-Selvon, Antoine, Lhenry-Yvon, Isabelle, Link, Katrin, Lopes, Luis, López, Rebeca, Casado, Aida López, Louedec, Karim, Lucero, Agustin, Malacari, Max, Mallamaci, Manuela, Maller, Jennifer, Mandat, Dusan, Mantsch, Paul, Mariazzi, Analisa, Marin, Vincent, Mariş, Ioana, Marsella, Giovanni, Martello, Daniele, Martinez, Humberto, Bravo, Oscar Martínez, Martraire, Diane, Meza, Jimmy Masías, Mathes, Hermann-Josef, Mathys, Sebastian, Matthews, James, Matthews, John, Matthiae, Giorgio, Maurizio, Daniela, Mayotte, Eric, Mazur, Peter, Medina, Carlos, Medina-Tanco, Gustavo, Meissner, Rebecca, Mello, Victor, Melo, Diego, Menshikov, Alexander, Messina, Stefano, Micheletti, Maria Isabel, Middendorf, Lukas, Minaya, Ignacio A., Miramonti, Lino, Mitrica, Bogdan, Molina-Bueno, Laura, Mollerach, Silvia, Montanet, François, Morello, Carlo, Mostafá, Miguel, Moura, Celio A., Muller, Marcio Aparecido, Müller, Gero, Müller, Sarah, Navas, Sergio, Necesal, Petr, Nellen, Lukas, Nelles, Anna, Neuser, Jens, Nguyen, Phong H., Niculescu-Oglinzanu, Mihai, Niechciol, Marcus, Niemietz, Lukas, Niggemann, Tim, Nitz, Dave, Nosek, Dalibor, Novotny, Vladimir, Nožka, Lyberis, Núñez, Luis, Ochilo, Livingstone, Oikonomou, Foteini, Olinto, Angela, Pacheco, Noelia, Selmi-Dei, Daniel Pakk, Palatka, Miroslav, Pallotta, Juan, Papenbreer, Philipp, Parente, Gonzalo, Parra, Alejandra, Paul, Thomas, Pech, Miroslav, Pękala, Jan, Pelayo, Rodrigo, Pepe, Iuri, Perrone, Lorenzo, Petermann, Emily, Peters, Christine, Petrera, Sergio, Petrov, Yevgeniy, Phuntsok, Jamyang, Piegaia, Ricardo, Pierog, Tanguy, Pieroni, Pablo, Pimenta, Mário, Pirronello, Valerio, Platino, Manuel, Plum, Matthias, Porcelli, Alessio, Porowski, Czeslaw, Prado, Raul Ribeiro, Privitera, Paolo, Prouza, Michael, Quel, Eduardo J, Querchfeld, Sven, Quinn, Sean, Rautenberg, Julian, Ravel, Olivier, Ravignani, Diego, Reinert, Darius, Revenu, Benoît, Ridky, Jan, Risse, Markus, Ristori, Pablo, Rizi, Vincenzo, de Carvalho, Washington Rodrigues, Rojo, Jorge Rubén Rodriguez, Rodríguez-Frías, Maria Dolores, Rogozin, Dmytro, Rosado, Jaime, Roth, Markus, Roulet, Esteban, Rovero, Adrian, Saffi, Steven J., Saftoiu, Alexandra, Salazar, Humberto, Saleh, Ahmed, Greus, Francisco Salesa, Salina, Gaetano, Gomez, Jose Sanabria, Sánchez, Federico, Sanchez-Lucas, Patricia, Santos, Edivaldo Moura, Santos, Eva, Sarazin, Fred, Sarkar, Biswaijt, Sarmento, Raul, Sarmiento-Cano, Christian, Sato, Ricardo, Scarso, Carlos, Schauer, Markus, Scherini, Viviana, Schieler, Harald, Schmidt, David, Scholten, Olaf, Schoorlemmer, Harm, Schovánek, Petr, Schröder, Frank G., Schulz, Alexander, Schulz, Johannes, Schumacher, Johannes, Sciutto, Sergio, Segreto, Alberto, Settimo, Mariangela, Shadkam, Amir, Shellard, Ronald C., Sigl, Guenter, Sima, Octavian, Śmiałkowski, Andrzej, Šmída, Radomir, Snow, Gregory, Sommers, Paul, Sonntag, Sebastian, Sorokin, J., Squartini, Ruben, Srivastava, Yogendra N., Stanca, Denis, Stanič, Samo, Stapleton, James, Stasielak, Jaroslaw, Stephan, Maurice, Stutz, Anne, Suarez, Federico, Durán, Mauricio Suarez, Suomijärvi, Tiina, Supanitsky, A. Daniel, Sutherland, Michael, Swain, John, Szadkowski, Zbigniew, Taborda, Oscar Alejandro, Tapia, Alex, Tepe, Andreas, Theodoro, Vanessa Menezes, Tibolla, Omar, Timmermans, Charles, Peixoto, Carlos J. Todero, Toma, Gabriel, Tomankova, Lenka, Tomé, Bernardo, Tonachini, Aurelio, Elipe, Guillermo Torralba, Machado, Diego Torres, Travnicek, Petr, Trini, Marta, Ulrich, Ralf, Unger, Michael, Urban, Martin, Galicia, Jose F. Valdés, Valiño, Ines, Valore, Laura, van Aar, Guus, van Bodegom, Patrick, Berg, Ad M. van den, van Velzen, Sjoert, van Vliet, Arjen, Varela, Enrique, Cárdenas, Bernardo Vargas, Varner, Gary, Vasquez, Rafael, Vázquez, Jose R., Vázquez, Ricardo, Veberič, Darko, Verzi, Valerio, Vicha, Jakub, Videla, Mariela, Villaseñor, Luis, Vlcek, Brian, Vorobiov, Serguei, Wahlberg, Hernan, Wainberg, Oscar, Walz, David, Watson, Alan, Weber, Marc, Weidenhaupt, Klaus, Weindl, Andreas, Welling, Christoph, Werner, Felix, Widom, Allan, Wiencke, Lawrence, Wilczyński, Henryk, Winchen, Tobias, Wittkowski, David, Wundheiler, Brian, Wykes, Sarka, Yang, Lili, Yapici, Tolga, Yushkov, Alexey, Zas, Enrique, Zavrtanik, Danilo, Zavrtanik, Marko, Zepeda, Arnulfo, Zimmermann, Benedikt, Ziolkowski, Michael, and Zuccarello, Francesca

Subjects
Astrophysics - High Energy Astrophysical Phenomena, Astrophysics - Instrumentation and Methods for Astrophysics
Abstract

The Auger Engineering Radio Array (AERA) is part of the Pierre Auger Observatory and is used to detect the radio emission of cosmic-ray air showers. These observations are compared to the data of the surface detector stations of the Observatory, which provide well-calibrated information on the cosmic-ray energies and arrival directions. The response of the radio stations in the 30 to 80 MHz regime has been thoroughly calibrated to enable the reconstruction of the incoming electric field. For the latter, the energy deposit per area is determined from the radio pulses at each observer position and is interpolated using a two-dimensional function that takes into account signal asymmetries due to interference between the geomagnetic and charge-excess emission components. The spatial integral over the signal distribution gives a direct measurement of the energy transferred from the primary cosmic ray into radio emission in the AERA frequency range. We measure 15.8 MeV of radiation energy for a 1 EeV air shower arriving perpendicularly to the geomagnetic field. This radiation energy -- corrected for geometrical effects -- is used as a cosmic-ray energy estimator. Performing an absolute energy calibration against the surface-detector information, we observe that this radio-energy estimator scales quadratically with the cosmic-ray energy as expected for coherent emission. We find an energy resolution of the radio reconstruction of 22% for the data set and 17% for a high-quality subset containing only events with at least five radio stations with signal., Comment: Replaced with published version. Added journal reference and DOI

Published
2015
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13. An improved limit to the diffuse flux of ultra-high energy neutrinos from the Pierre Auger Observatory

Author

The Pierre Auger Collaboration, Aab, Alexander, Abreu, Pedro, Aglietta, Marco, Ahn, Eun-Joo, Samarai, Imen Al, Albuquerque, Ivone, Allekotte, Ingomar, Allison, Patrick, Almela, Alejandro, Castillo, Jesus Alvarez, Alvarez-Muñiz, Jaime, Batista, Rafael Alves, Ambrosio, Michelangelo, Aminaei, Amin, Anchordoqui, Luis, Andringa, Sofia, Aramo, Carla, Aranda, Victor Manuel, Arqueros, Fernando, Arsene, Nicusor, Asorey, Hernán Gonzalo, Assis, Pedro, Aublin, Julien, Ave, Maximo, Avenier, Michel, Avila, Gualberto, Awal, Nafiun, Badescu, Alina Mihaela, Barber, Kerri B, Bäuml, Julia, Baus, Colin, Beatty, Jim, Becker, Karl Heinz, Bellido, Jose A, Berat, Corinne, Bertaina, Mario Edoardo, Bertou, Xavier, Biermann, Peter, Billoir, Pierre, Blaess, Simon G, Blanco, Alberto, Blanco, Miguel, Bleve, Carla, Blümer, Hans, Boháčová, Martina, Boncioli, Denise, Bonifazi, Carla, Borodai, Nataliia, Brack, Jeffrey, Brancus, Iliana, Bridgeman, Ariel, Brogueira, Pedro, Brown, William C, Buchholz, Peter, Bueno, Antonio, Buitink, Stijn, Buscemi, Mario, Caballero-Mora, Karen S, Caccianiga, Barbara, Caccianiga, Lorenzo, Candusso, Marina, Caramete, Laurentiu, Caruso, Rossella, Castellina, Antonella, Cataldi, Gabriella, Cazon, Lorenzo, Cester, Rosanna, Chavez, Alan G, Chiavassa, Andrea, Chinellato, Jose Augusto, Chudoba, Jiri, Cilmo, Marco, Clay, Roger W, Cocciolo, Giuseppe, Colalillo, Roberta, Coleman, Alan, Collica, Laura, Coluccia, Maria Rita, Conceição, Ruben, Contreras, Fernando, Cooper, Mathew J, Cordier, Alain, Coutu, Stephane, Covault, Corbin, Cronin, James, Dallier, Richard, Daniel, Bruno, Dasso, Sergio, Daumiller, Kai, Dawson, Bruce R, de Almeida, Rogerio M, de Jong, Sijbrand J, De Mauro, Giuseppe, Neto, Joao de Mello, De Mitri, Ivan, de Oliveira, Jaime, de Souza, Vitor, del Peral, Luis, Deligny, Olivier, Dembinski, Hans, Dhital, Niraj, Di Giulio, Claudio, Di Matteo, Armando, Diaz, Johana Chirinos, Castro, Mary Lucia Díaz, Diogo, Francisco, Dobrigkeit, Carola, Docters, Wendy, D'Olivo, Juan Carlos, Dorofeev, Alexei, Hasankiadeh, Qader Dorosti, Dova, Maria Teresa, Ebr, Jan, Engel, Ralph, Erdmann, Martin, Erfani, Mona, Escobar, Carlos O, Espadanal, Joao, Etchegoyen, Alberto, Falcke, Heino, Fang, Ke, Farrar, Glennys, Fauth, Anderson, Fazzini, Norberto, Ferguson, Andrew P, Fernandes, Mateus, Fick, Brian, Figueira, Juan Manuel, Filevich, Alberto, Filipčič, Andrej, Fox, Brendan, Fratu, Octavian, Freire, Martín Miguel, Fuchs, Benjamin, Fujii, Toshihiro, García, Beatriz, Garcia-Pinto, Diego, Gate, Florian, Gemmeke, Hartmut, Gherghel-Lascu, Alexandru, Ghia, Piera Luisa, Giaccari, Ugo, Giammarchi, Marco, Giller, Maria, Głas, Dariusz, Glaser, Christian, Glass, Henry, Golup, Geraldina, Berisso, Mariano Gómez, Vitale, Primo F Gómez, González, Nicolás, Gookin, Ben, Gordon, Jacob, Gorgi, Alessio, Gorham, Peter, Gouffon, Philippe, Griffith, Nathan, Grillo, Aurelio, Grubb, Trent D, Guardincerri, Yann, Guarino, Fausto, Guedes, Germano, Hampel, Matías Rolf, Hansen, Patricia, Harari, Diego, Harrison, Thomas A, Hartmann, Sebastian, Harton, John, Haungs, Andreas, Hebbeker, Thomas, Heck, Dieter, Heimann, Philipp, Herve, Alexander E, Hill, Gary C, Hojvat, Carlos, Hollon, Nicholas, Holt, Ewa, Homola, Piotr, Hörandel, Jörg, Horvath, Pavel, Hrabovský, Miroslav, Huber, Daniel, Huege, Tim, Insolia, Antonio, Isar, Paula Gina, Jandt, Ingolf, Jansen, Stefan, Jarne, Cecilia, Johnsen, Jeffrey A, Josebachuili, Mariela, Kääpä, Alex, Kambeitz, Olga, Kampert, Karl Heinz, Kasper, Peter, Katkov, Igor, Kégl, Balazs, Keilhauer, Bianca, Keivani, Azadeh, Kemp, Ernesto, Kieckhafer, Roger, Klages, Hans, Kleifges, Matthias, Kleinfeller, Jonny, Krause, Raphael, Krohm, Nicole, Krömer, Oliver, Kuempel, Daniel, Kunka, Norbert, LaHurd, Danielle, Latronico, Luca, Lauer, Robert, Lauscher, Markus, Lautridou, Pascal, Coz, Sandra Le, Lebrun, Didier, Lebrun, Paul, de Oliveira, Marcelo Augusto Leigui, Letessier-Selvon, Antoine, Lhenry-Yvon, Isabelle, Link, Katrin, Lopes, Luis, López, Rebeca, Casado, Aida López, Louedec, Karim, Lu, Lu, Lucero, Agustin, Malacari, Max, Maldera, Simone, Mallamaci, Manuela, Maller, Jennifer, Mandat, Dusan, Mantsch, Paul, Mariazzi, Analisa, Marin, Vincent, Mariş, Ioana, Marsella, Giovanni, Martello, Daniele, Martin, Lilian, Martinez, Humberto, Bravo, Oscar Martínez, Martraire, Diane, Meza, Jimmy Masías, Mathes, Hermann-Josef, Mathys, Sebastian, Matthews, James, Matthews, John, Matthiae, Giorgio, Maurel, Detlef, Maurizio, Daniela, Mayotte, Eric, Mazur, Peter, Medina, Carlos, Medina-Tanco, Gustavo, Meissner, Rebecca, Mello, Victor, Melo, Diego, Menshikov, Alexander, Messina, Stefano, Meyhandan, Rishi, Micheletti, Maria Isabel, Middendorf, Lukas, Minaya, Ignacio A, Miramonti, Lino, Mitrica, Bogdan, Molina-Bueno, Laura, Mollerach, Silvia, Montanet, François, Morello, Carlo, Mostafá, Miguel, Moura, Celio A, Muller, Marcio Aparecido, Müller, Gero, Müller, Sarah, Mussa, Roberto, Navarra, Gianni, Navarro, Jose Luis, Navas, Sergio, Necesal, Petr, Nellen, Lukas, Nelles, Anna, Neuser, Jens, Nguyen, Phong H, Niculescu-Oglinzanu, Mihai, Niechciol, Marcus, Niemietz, Lukas, Niggemann, Tim, Nitz, Dave, Nosek, Dalibor, Novotny, Vladimir, Nožka, Lyberis, Ochilo, Livingstone, Oikonomou, Foteini, Olinto, Angela, Pacheco, Noelia, Selmi-Dei, Daniel Pakk, Palatka, Miroslav, Pallotta, Juan, Papenbreer, Philipp, Parente, Gonzalo, Parra, Alejandra, Paul, Thomas, Pech, Miroslav, Pękala, Jan, Pelayo, Rodrigo, Pepe, Iuri, Perrone, Lorenzo, Petermann, Emily, Peters, Christine, Petrera, Sergio, Petrov, Yevgeniy, Phuntsok, Jamyang, Piegaia, Ricardo, Pierog, Tanguy, Pieroni, Pablo, Pimenta, Mário, Pirronello, Valerio, Platino, Manuel, Plum, Matthias, Porcelli, Alessio, Porowski, Czeslaw, Prado, Raul Ribeiro, Privitera, Paolo, Prouza, Michael, Purrello, Victor, Quel, Eduardo J, Querchfeld, Sven, Quinn, Sean, Rautenberg, Julian, Ravel, Olivier, Ravignani, Diego, Revenu, Benoît, Ridky, Jan, Riggi, Simone, Risse, Markus, Ristori, Pablo, Rizi, Vincenzo, de Carvalho, Washington Rodrigues, Fernandez, Gonzalo Rodriguez, Rojo, Jorge Rubén Rodriguez, Rodríguez-Frías, Maria Dolores, Rogozin, Dmytro, Rosado, Jaime, Roth, Markus, Roulet, Esteban, Rovero, Adrian, Saffi, Steven J, Saftoiu, Alexandra, Salamida, Francesco, Salazar, Humberto, Saleh, Ahmed, Greus, Francisco Salesa, Salina, Gaetano, Sánchez, Federico, Sanchez-Lucas, Patricia, Santos, Edivaldo Moura, Santos, Eva, Sarazin, Fred, Sarkar, Biswaijt, Sarmento, Raul, Sato, Ricardo, Scarso, Carlos, Schauer, Markus, Scherini, Viviana, Schieler, Harald, Schiffer, Peter, Schmidt, David, Scholten, Olaf, Schoorlemmer, Harm, Schovánek, Petr, Schröder, Frank G, Schulz, Alexander, Schulz, Johannes, Schumacher, Johannes, Sciutto, Sergio, Segreto, Alberto, Settimo, Mariangela, Shadkam, Amir, Shellard, Ronald C, Sidelnik, Iván, Sigl, Guenter, Sima, Octavian, Śmiałkowski, Andrzej, Šmída, Radomir, Snow, Gregory, Sommers, Paul, Sorokin, J, Squartini, Ruben, Srivastava, Yogendra N, Stanca, Denis, Stanič, Samo, Stapleton, James, Stasielak, Jaroslaw, Stephan, Maurice, Stutz, Anne, Suarez, Federico, Suomijärvi, Tiina, Supanitsky, A Daniel, Sutherland, Michael, Swain, John, Szadkowski, Zbigniew, Taborda, Oscar Alejandro, Tapia, Alex, Tepe, Andreas, Theodoro, Vanessa Menezes, Tiffenberg, Javier, Timmermans, Charles, Peixoto, Carlos J Todero, Toma, Gabriel, Tomankova, Lenka, Tomé, Bernardo, Tonachini, Aurelio, Elipe, Guillermo Torralba, Machado, Diego Torres, Travnicek, Petr, Ulrich, Ralf, Unger, Michael, Urban, Martin, Galicia, Jose F Valdés, Valiño, Ines, Valore, Laura, van Aar, Guus, van Bodegom, Patrick, Berg, Ad M van den, van Velzen, Sjoert, van Vliet, Arjen, Varela, Enrique, Cárdenas, Bernardo Vargas, Varner, Gary, Vasquez, Rafael, Vázquez, Jose R, Vázquez, Ricardo, Veberič, Darko, Verzi, Valerio, Vicha, Jakub, Videla, Mariela, Villaseñor, Luis, Vlcek, Brian, Vorobiov, Serguei, Wahlberg, Hernan, Wainberg, Oscar, Walz, David, Watson, Alan, Weber, Marc, Weidenhaupt, Klaus, Weindl, Andreas, Werner, Felix, Widom, Allan, Wiencke, Lawrence, Wilczyński, Henryk, Winchen, Tobias, Wittkowski, David, Wundheiler, Brian, Wykes, Sarka, Yang, Lili, Yapici, Tolga, Yushkov, Alexey, Zas, Enrique, Zavrtanik, Danilo, Zavrtanik, Marko, Zepeda, Arnulfo, Zhu, Yue, Zimmermann, Benedikt, Ziolkowski, Michael, and Zuccarello, Francesca

Subjects
Astrophysics - High Energy Astrophysical Phenomena
Abstract

Neutrinos in the cosmic ray flux with energies near 1 EeV and above are detectable with the Surface Detector array of the Pierre Auger Observatory. We report here on searches through Auger data from 1 January 2004 until 20 June 2013. No neutrino candidates were found, yielding a limit to the diffuse flux of ultra-high energy neutrinos that challenges the Waxman-Bahcall bound predictions. Neutrino identification is attempted using the broad time-structure of the signals expected in the SD stations, and is efficiently done for neutrinos of all flavors interacting in the atmosphere at large zenith angles, as well as for "Earth-skimming" neutrino interactions in the case of tau neutrinos. In this paper the searches for downward-going neutrinos in the zenith angle bins $60^\circ-75^\circ$ and $75^\circ-90^\circ$ as well as for upward-going neutrinos, are combined to give a single limit. The $90\%$ C.L. single-flavor limit to the diffuse flux of ultra-high energy neutrinos with an $E^{-2}$ spectrum in the energy range $1.0 \times 10^{17}$ eV - $2.5 \times 10^{19}$ eV is $E_\nu^2 dN_\nu/dE_\nu < 6.4 \times 10^{-9}~ {\rm GeV~ cm^{-2}~ s^{-1}~ sr^{-1}}$., Comment: Replaced with published version. Added journal reference and DOI

Published
2015
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14. Measurement of the cosmic ray spectrum above $4{\times}10^{18}$ eV using inclined events detected with the Pierre Auger Observatory

Author

The Pierre Auger Collaboration, Aab, Alexander, Abreu, Pedro, Aglietta, Marco, Ahn, Eun-Joo, Samarai, Imen Al, Albuquerque, Ivone, Allekotte, Ingomar, Allison, Patrick, Almela, Alejandro, Castillo, Jesus Alvarez, Alvarez-Muñiz, Jaime, Batista, Rafael Alves, Ambrosio, Michelangelo, Aminaei, Amin, Anchordoqui, Luis, Andringa, Sofia, Aramo, Carla, Aranda, Victor Manuel, Arqueros, Fernando, Arsene, Nicusor, Asorey, Hernán Gonzalo, Assis, Pedro, Aublin, Julien, Ave, Maximo, Avenier, Michel, Avila, Gualberto, Awal, Nafiun, Badescu, Alina Mihaela, Barber, Kerri B, Bäuml, Julia, Baus, Colin, Beatty, Jim, Becker, Karl Heinz, Bellido, Jose A, Berat, Corinne, Bertaina, Mario Edoardo, Bertou, Xavier, Biermann, Peter, Billoir, Pierre, Blaess, Simon G, Blanco, Alberto, Blanco, Miguel, Bleve, Carla, Blümer, Hans, Boháčová, Martina, Boncioli, Denise, Bonifazi, Carla, Borodai, Nataliia, Brack, Jeffrey, Brancus, Iliana, Bridgeman, Ariel, Brogueira, Pedro, Brown, William C, Buchholz, Peter, Bueno, Antonio, Buitink, Stijn, Buscemi, Mario, Caballero-Mora, Karen S, Caccianiga, Barbara, Caccianiga, Lorenzo, Candusso, Marina, Caramete, Laurentiu, Caruso, Rossella, Castellina, Antonella, Cataldi, Gabriella, Cazon, Lorenzo, Cester, Rosanna, Chavez, Alan G, Chiavassa, Andrea, Chinellato, Jose Augusto, Chudoba, Jiri, Cilmo, Marco, Clay, Roger W, Cocciolo, Giuseppe, Colalillo, Roberta, Coleman, Alan, Collica, Laura, Coluccia, Maria Rita, Conceição, Ruben, Contreras, Fernando, Cooper, Mathew J, Cordier, Alain, Coutu, Stephane, Covault, Corbin, Cronin, James, Dallier, Richard, Daniel, Bruno, Dasso, Sergio, Daumiller, Kai, Dawson, Bruce R, de Almeida, Rogerio M, de Jong, Sijbrand J, De Mauro, Giuseppe, Neto, Joao de Mello, De Mitri, Ivan, de Oliveira, Jaime, de Souza, Vitor, del Peral, Luis, Deligny, Olivier, Dembinski, Hans, Dhital, Niraj, Di Giulio, Claudio, Di Matteo, Armando, Diaz, Johana Chirinos, Castro, Mary Lucia Díaz, Diogo, Francisco, Dobrigkeit, Carola, Docters, Wendy, D'Olivo, Juan Carlos, Dorofeev, Alexei, Hasankiadeh, Qader Dorosti, Dova, Maria Teresa, Ebr, Jan, Engel, Ralph, Erdmann, Martin, Erfani, Mona, Escobar, Carlos O, Espadanal, Joao, Etchegoyen, Alberto, Falcke, Heino, Fang, Ke, Farrar, Glennys, Fauth, Anderson, Fazzini, Norberto, Ferguson, Andrew P, Fernandes, Mateus, Fick, Brian, Figueira, Juan Manuel, Filevich, Alberto, Filipčič, Andrej, Fox, Brendan, Fratu, Octavian, Freire, Martín Miguel, Fuchs, Benjamin, Fujii, Toshihiro, García, Beatriz, Garcia-Pinto, Diego, Gate, Florian, Gemmeke, Hartmut, Gherghel-Lascu, Alexandru, Ghia, Piera Luisa, Giaccari, Ugo, Giammarchi, Marco, Giller, Maria, Głas, Dariusz, Glaser, Christian, Glass, Henry, Golup, Geraldina, Berisso, Mariano Gómez, Vitale, Primo F Gómez, González, Nicolás, Gookin, Ben, Gordon, Jacob, Gorgi, Alessio, Gorham, Peter, Gouffon, Philippe, Griffith, Nathan, Grillo, Aurelio, Grubb, Trent D, Guarino, Fausto, Guedes, Germano, Hampel, Matías Rolf, Hansen, Patricia, Harari, Diego, Harrison, Thomas A, Hartmann, Sebastian, Harton, John, Haungs, Andreas, Hebbeker, Thomas, Heck, Dieter, Heimann, Philipp, Herve, Alexander E, Hill, Gary C, Hojvat, Carlos, Hollon, Nicholas, Holt, Ewa, Homola, Piotr, Hörandel, Jörg, Horvath, Pavel, Hrabovský, Miroslav, Huber, Daniel, Huege, Tim, Insolia, Antonio, Isar, Paula Gina, Jandt, Ingolf, Jansen, Stefan, Jarne, Cecilia, Johnsen, Jeffrey A, Josebachuili, Mariela, Kääpä, Alex, Kambeitz, Olga, Kampert, Karl Heinz, Kasper, Peter, Katkov, Igor, Kégl, Balazs, Keilhauer, Bianca, Keivani, Azadeh, Kemp, Ernesto, Kieckhafer, Roger, Klages, Hans, Kleifges, Matthias, Kleinfeller, Jonny, Krause, Raphael, Krohm, Nicole, Krömer, Oliver, Kuempel, Daniel, Kunka, Norbert, LaHurd, Danielle, Latronico, Luca, Lauer, Robert, Lauscher, Markus, Lautridou, Pascal, Coz, Sandra Le, Lebrun, Didier, Lebrun, Paul, de Oliveira, Marcelo Augusto Leigui, Letessier-Selvon, Antoine, Lhenry-Yvon, Isabelle, Link, Katrin, Lopes, Luis, López, Rebeca, Casado, Aida López, Louedec, Karim, Lu, Lu, Lucero, Agustin, Malacari, Max, Maldera, Simone, Mallamaci, Manuela, Maller, Jennifer, Mandat, Dusan, Mantsch, Paul, Mariazzi, Analisa, Marin, Vincent, Mariş, Ioana, Marsella, Giovanni, Martello, Daniele, Martin, Lilian, Martinez, Humberto, Bravo, Oscar Martínez, Martraire, Diane, Meza, Jimmy Masías, Mathes, Hermann-Josef, Mathys, Sebastian, Matthews, James, Matthews, John, Matthiae, Giorgio, Maurel, Detlef, Maurizio, Daniela, Mayotte, Eric, Mazur, Peter, Medina, Carlos, Medina-Tanco, Gustavo, Meissner, Rebecca, Mello, Victor, Melo, Diego, Menshikov, Alexander, Messina, Stefano, Meyhandan, Rishi, Micheletti, Maria Isabel, Middendorf, Lukas, Minaya, Ignacio A, Miramonti, Lino, Mitrica, Bogdan, Molina-Bueno, Laura, Mollerach, Silvia, Montanet, François, Morello, Carlo, Mostafá, Miguel, Moura, Celio A, Muller, Marcio Aparecido, Müller, Gero, Müller, Sarah, Mussa, Roberto, Navarra, Gianni, Navas, Sergio, Necesal, Petr, Nellen, Lukas, Nelles, Anna, Neuser, Jens, Newton, David, Nguyen, Phong H, Niculescu-Oglinzanu, Mihai, Niechciol, Marcus, Niemietz, Lukas, Niggemann, Tim, Nitz, Dave, Nosek, Dalibor, Novotny, Vladimir, Nožka, Lyberis, Ochilo, Livingstone, Oikonomou, Foteini, Olinto, Angela, Olmos-Gilbaja, Victor, Pacheco, Noelia, Selmi-Dei, Daniel Pakk, Palatka, Miroslav, Pallotta, Juan, Papenbreer, Philipp, Parente, Gonzalo, Parra, Alejandra, Paul, Thomas, Pech, Miroslav, Pękala, Jan, Pelayo, Rodrigo, Pepe, Iuri, Perrone, Lorenzo, Petermann, Emily, Peters, Christine, Petrera, Sergio, Petrov, Yevgeniy, Phuntsok, Jamyang, Piegaia, Ricardo, Pierog, Tanguy, Pieroni, Pablo, Pimenta, Mário, Pirronello, Valerio, Platino, Manuel, Plum, Matthias, Porcelli, Alessio, Porowski, Czeslaw, Prado, Raul Ribeiro, Privitera, Paolo, Prouza, Michael, Purrello, Victor, Quel, Eduardo J, Querchfeld, Sven, Quinn, Sean, Rautenberg, Julian, Ravel, Olivier, Ravignani, Diego, Revenu, Benoît, Ridky, Jan, Riggi, Simone, Risse, Markus, Ristori, Pablo, Rizi, Vincenzo, de Carvalho, Washington Rodrigues, Fernandez, Gonzalo Rodriguez, Rojo, Jorge Rubén Rodriguez, Rodríguez-Frías, Maria Dolores, Rogozin, Dmytro, Rosado, Jaime, Roth, Markus, Roulet, Esteban, Rovero, Adrian, Saffi, Steven J, Saftoiu, Alexandra, Salamida, Francesco, Salazar, Humberto, Saleh, Ahmed, Greus, Francisco Salesa, Salina, Gaetano, Sánchez, Federico, Sanchez-Lucas, Patricia, Santos, Edivaldo Moura, Santos, Eva, Sarazin, Fred, Sarkar, Biswaijt, Sarmento, Raul, Sato, Ricardo, Scarso, Carlos, Schauer, Markus, Scherini, Viviana, Schieler, Harald, Schiffer, Peter, Schmidt, David, Scholten, Olaf, Schoorlemmer, Harm, Schovánek, Petr, Schröder, Frank G, Schulz, Alexander, Schulz, Johannes, Schumacher, Johannes, Sciutto, Sergio, Segreto, Alberto, Settimo, Mariangela, Shadkam, Amir, Shellard, Ronald C, Sidelnik, Iván, Sigl, Guenter, Sima, Octavian, Śmiałkowski, Andrzej, Šmída, Radomir, Snow, Gregory, Sommers, Paul, Sorokin, J, Squartini, Ruben, Srivastava, Yogendra N, Stanca, Denis, Stanič, Samo, Stapleton, James, Stasielak, Jaroslaw, Stephan, Maurice, Stutz, Anne, Suarez, Federico, Suomijärvi, Tiina, Supanitsky, A Daniel, Sutherland, Michael, Swain, John, Szadkowski, Zbigniew, Taborda, Oscar Alejandro, Tapia, Alex, Tepe, Andreas, Theodoro, Vanessa Menezes, Timmermans, Charles, Peixoto, Carlos J Todero, Toma, Gabriel, Tomankova, Lenka, Tomé, Bernardo, Tonachini, Aurelio, Elipe, Guillermo Torralba, Machado, Diego Torres, Travnicek, Petr, Ulrich, Ralf, Unger, Michael, Urban, Martin, Galicia, Jose F Valdés, Valiño, Ines, Valore, Laura, van Aar, Guus, van Bodegom, Patrick, Berg, Ad M van den, van Velzen, Sjoert, van Vliet, Arjen, Varela, Enrique, Cárdenas, Bernardo Vargas, Varner, Gary, Vasquez, Rafael, Vázquez, Jose R, Vázquez, Ricardo, Veberič, Darko, Verzi, Valerio, Vicha, Jakub, Videla, Mariela, Villaseñor, Luis, Vlcek, Brian, Vorobiov, Serguei, Wahlberg, Hernan, Wainberg, Oscar, Walz, David, Watson, Alan, Weber, Marc, Weidenhaupt, Klaus, Weindl, Andreas, Werner, Felix, Widom, Allan, Wiencke, Lawrence, Wilczyński, Henryk, Winchen, Tobias, Wittkowski, David, Wundheiler, Brian, Wykes, Sarka, Yang, Lili, Yapici, Tolga, Yushkov, Alexey, Zas, Enrique, Zavrtanik, Danilo, Zavrtanik, Marko, Zepeda, Arnulfo, Zhu, Yue, Zimmermann, Benedikt, Ziolkowski, Michael, and Zuccarello, Francesca

Subjects
Astrophysics - High Energy Astrophysical Phenomena, High Energy Physics - Experiment
Abstract

A measurement of the cosmic-ray spectrum for energies exceeding $4{\times}10^{18}$ eV is presented, which is based on the analysis of showers with zenith angles greater than $60^{\circ}$ detected with the Pierre Auger Observatory between 1 January 2004 and 31 December 2013. The measured spectrum confirms a flux suppression at the highest energies. Above $5.3{\times}10^{18}$ eV, the "ankle", the flux can be described by a power law $E^{-\gamma}$ with index $\gamma=2.70 \pm 0.02 \,\text{(stat)} \pm 0.1\,\text{(sys)}$ followed by a smooth suppression region. For the energy ($E_\text{s}$) at which the spectral flux has fallen to one-half of its extrapolated value in the absence of suppression, we find $E_\text{s}=(5.12\pm0.25\,\text{(stat)}^{+1.0}_{-1.2}\,\text{(sys)}){\times}10^{19}$ eV., Comment: Replaced with published version. Added journal reference and DOI

Published
2015
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15. The magnetic structure of surges in small-scale emerging flux regions

Author

MacTaggart, David, Guglielmino, Salvo, Haynes, Andrew, Simitev, Radostin, and Zuccarello, Francesca

Subjects
Astrophysics - Solar and Stellar Astrophysics, Physics - Fluid Dynamics, Physics - Plasma Physics
Abstract

Aims: To investigate the relationship between surges and magnetic reconnection during the emergence of small-scale active regions. In particular, to examine how the large-scale geometry of the magnetic field, shaped by different phases of reconnection, guides the flowing of surges. Methods: We present three flux emergence models. The first model, and the simplest, consists of a region emerging into a horizontal ambient field that is initially parallel to the top of the emerging region. The second model is the same as the first but with an extra smaller emerging region which perturbs the main region. This is added to create a more complex magnetic topology and to test how this complicates the development of surges compared to the first model. The last model has a non-uniform ambient magnetic field to model the effects of emergence near a sunspot field and impose asymmetry on the system through the ambient magnetic field. At each stage, we trace the magnetic topology to identify the locations of reconnection. This allows for field lines to be plotted from different topological regions, highlighting how their geometry affects the development of surges. Results: In the first model, we identify distinct phases of reconnection. Each phase is associated with a particular geometry for the magnetic field and this determines the paths of the surges. The second model follows a similar pattern to the first but with a more complex magnetic topology and extra eruptions. The third model highlights how an asymmetric ambient field can result in preferred locations for reconnection, subsequently guiding the direction of surges., Comment: Accepted for A&A

Published
2015
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16. The role of filament activation in a solar eruption

Author

da Costa, Fatima Rubio, Zuccarello, Francesca, Fletcher, Lyndsay, Romano, Paolo, and Labrosse, Nicolas

Subjects
Astrophysics - Solar and Stellar Astrophysics
Abstract

Observations show that the mutual relationship between filament eruptions and solar flares cannot be described in terms of an unique scenario. In some cases, the eruption of a filament appears to trigger a flare, while in others the observations are more consistent with magnetic reconnection that produces both the flare observational signatures (e.g., ribbons, plasma jets, post-flare loops, etc.) and later the destabilization and eruption of a filament. We study an event which occurred in NOAA 8471, where a flare and the activation of (at least) two filaments were observed on 28 February 1999. By using imaging data acquired in the 1216, 1600, 171 and 195 \AA\ TRACE channels and by BBSO in the continnum and in H$\alpha$, a morphological study of the event is carried out. Using TRACE 1216 and 1600 \AA\ data, an estimate of the "pure" Ly$\alpha$ power is obtained. The extrapolation of the magnetic field lines is done using the SOHO/MDI magnetograms and assuming a potential field. The potential magnetic field extrapolation indicates that the field line connectivity changes after the flare. The event is triggered by the destabilization of a filament located between the two polarities of a $\delta$ spot. This destabilization involves the magnetic arcades of the active region and causes the eruption of a second filament, that gives rise to a CME and to plasma motions over a supergranular cell. We conclude that in this event the two filaments play an active and decisive role, albeit in different stages of the phenomenon, in fact the destabilization of one filament causes brightenings, reconnection and ribbons, while the second one, whose eruption is caused by the field reconfiguration resulting from the previous reconnection, undergoes the greatest changes and causes the CME., Comment: 11 pages, 16 figures

Published
2014
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17. Observational evidence of torus instability as trigger mechanism for coronal mass ejections: the 2011 August 4 filament eruption

Author

Zuccarello, Francesco P., Seaton, Daniel B., Mierla, Marilena, Poedts, Stefaan, Rachmeler, Laurel A., Romano, Paolo, and Zuccarello, Francesca

Subjects
Astrophysics - Solar and Stellar Astrophysics
Abstract

Solar filaments are magnetic structures often observed in the solar atmosphere and consist of plasma that is cooler and denser than their surroundings. They are visible for days -- and even weeks -- which suggests that they are often in equilibrium with their environment before disappearing or erupting. Several eruption models have been proposed that aim to reveal what mechanism causes (or triggers) these solar eruptions. Validating these models through observations represents a fundamental step in our understanding of solar eruptions. We present an analysis of the observation of a filament eruption that agrees with the torus instability model. This model predicts that a magnetic flux rope embedded in an ambient field undergoes an eruption when the axis of the flux rope reaches a critical height that depends on the topology of the ambient field. We use the two vantage points of SDO and STEREO to reconstruct the three-dimensional shape of the filament, to follow its morphological evolution and to determine its height just before eruption. The magnetograms acquired by SDO/HMI are used to infer the topology of the ambient field and to derive the critical height for the onset of the torus instability. Our analysis shows that the torus instability is the trigger of the eruption. We also find that some pre-eruptive processes, such as magnetic reconnection during the observed flares and flux cancellation at the neutral line, facilitated the eruption by bringing the filament to a region where the magnetic field was more vulnerable to the torus instability., Comment: 11 pages, 9 figures, to appear in The Astrophysical Journal

Published
2014
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18. IRIS Observations of Magnetic Interactions in the Solar Atmosphere Between Preexisting and Emerging Magnetic Fields. II. UV Emission Properties

Author

Guglielmino, Salvo L, Young, Peter R, and Zuccarello, Francesca

Subjects
Solar Physics
Abstract

Multiwavelength ultraviolet (UV) observations by the Interface Region Imaging Spectrograph satellite in active region NOAA 12529 have recently pointed out the presence of long-lasting brightenings, akin to UV bursts, and simultaneous plasma ejections occurring in the upper chromosphere and transition region during secondary flux emergence. These signatures have been interpreted as evidence of small-scale, recurrent magnetic reconnection episodes between the emerging flux region (EFR) and the preexisting plage field. Here we characterize the UV emission of these strong, intermittent brightenings and study the surge activity above the chromospheric arch filament system (AFS) overlying the EFR. We analyze the surges and the cospatial brightenings observed at different wavelengths. We find an asymmetry in the emission between the blue and red wings of the Si iv λ1402 Å and Mg ii k λ2796.3 lines, which clearly outlines the dynamics of the structures above the AFS that form during the small-scale eruptive phenomena. We also detect a correlation between the Doppler velocity and skewness of the Si iv λλ1394 and 1402 line profiles in the UV burst pixels. Finally, we show that genuine emission in the Fe xii λ1349.4 line is cospatial to the Si iv brightenings. This definitely reveals a pure coronal counterpart to the reconnection event.

Published
2019
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