News Sito Bologna in Inglese
Mauro Villa has been elected spokesperson of the FOOT experiment for the next three years. Congratulations to Mauro from the whole INFN Bologna Division and a “good luck” for the success of FOOT in the panorama of hadrontherapy and radiation protection.
The new AMS-02 precision measurement of the cosmic-ray Fluorine flux shows a possible difference in the propagation of light and heavy cosmic-ray species.
The article published on PRL and selected as Editor’s Suggestion, is available in open-access at the address:
https://journals.aps.org/prl/abstract/10.1103/PysRevLett.126.081102?ft=1
The AMS Bologna group, involved in the measurement of cosmic ray nuclei, contributed directly to this publication with a cross-check analysis.
Since 2005, at the end of September, thousands of researchers have stormed the streets of hundreds of European cities during the European Researchers Night. During these nights the researchers explained their work, they told their stories, they shared their life with the general public in an informal and easy context, focusing on the fun that can come from doing science.
This year the Researchers Night is a little different. This year the event is scheduled for the 27 of November 2020, instead of September. Additionally the event has been changed to be followed remotely from your home.
Even if this gathering will be virtual the Night will be characterized by experiment, live demonstrations, visits, conference, seminars, etcetera. All of this will be accessible through the web page: https://notte-dei-ricercatori.sharevent.it/it-IT.
INFN will participate with 5 virtual spaces named: “c’è nebbia e nebbia”, “boccino d’oro o di latte”, “i raggi cosmici polari”, “intelligenza artificiale per la fisica delle alte energie”, and “curiosità della fisica e della natura”. Many INFN researches will be also available for the scientific speed-date, a private conversation between scientists and the interested people.
The hadron collider LHC ended its second period of data taking at the end of 2018 after a successful three-year run (2015:2018 Run 2). Since then, during the shutdown of the world largest particle accelerator several important upgrade of the accelerator complex and of the detectors have been carried out. Obviously also these operations were slowed down by the pandemic due to Sars-Cov-2 virus and consequent restrictions.
The time of flight (TOF) detector of the ALICE experiment has been built under leadership of ALICE group in Bologna. Since July the TOF ALICE group completed upgrades of the readout electronics. They included the production of a new readout card, designed by INFN Bologna, that houses high-speed optical links.
The TOF detector was gradually turned on during Summer. After many commissioning operations, the group has completed this week a first data taking observing the time-of-flight of the muons. These are particles produced by the interaction of cosmic rays with the atmosphere nuclei and able to cross two opposite modules of the TOF at a distance of around 8 meters. In the figure it is reported the difference between the time-of-flight measured and the expected one, based on the distance between the two channels hit on the detector.
At the LHC particle beams (and collisions) are foreseen to restart only since February 2020. During commissioning phase it is standard practice to use these particles coming from cosmic rays. Among the many sub-systems in ALICE currently completing their upgrade programme, the TOF is the first detector, with upgraded electronics, already restarting such measures, finally observing again particles inside the detector!
The TOF team was able to perform the measurement controlling remotely all the operations, with personnel connected from Bologna and CERN offices, or from private homes, but no presence was required at the experimental site in Saint-Genis-Pouilly where the ALICE experiment is.
Francesca Bellini, a member of the ALICE Collaboration, was selected as one of the recipients of the prestigious ERC Starting Grants assigned by the European Research Council in 2020 [1].
Francesca got her Master Degree and her PhD at Bologna University and she was then affiliated with INFN Bologna until 2017, while holding post-doc grants at Bologna University. In 2017-2020 she is Research fellow at CERN and, thanks to a Marie Sklodowska-Curie Fellowship, she was host at Bologna University for six months, working with ALICE-TOF group.
She started her career within ALICE, working on the development of the Quality Assurance procedures for the time-of-flight (TOF) detector, which is under Bologna INFN responsibility.
She then played a key role on several measurements related to the production of light flavours and hadronic resonances in the different collision systems tested at the LHC: proton-proton, proton-nucleus and nucleus-nucleus. She served in different coordinating roles for physics analyses in the Collaboration, including as convener of the Physics Working Group “Light flavor”.
During last years Francesca moved her research interests to the the study of the mechanisms driving the formation of light nuclei and anti-nuclei in high energy collisions. Thanks to the grant of approximately 1.4 milion of Euro coming from this ERC Starting Grant, Francesca will now have the possibility to lead a new research group for five years in the project CosmicAntiNuclei (submitted in collaboration with the Technical University of Munich). The project will exploit data gathered from ALICE during LHC Run 3. Its main goal is to clarify the mechanisms of nuclear cluster formation, thanks to high precision measurements of anti-Helium. This research is expected to have important applications for the study of cosmic rays and the search for dark matter.
The ERC assigned 436 ERC Starting Grants across the whole Europe following an extremely high-competition process (3272 applications were submitted).
By country, Italy is second among winners of the grants and Francesca Bellini is one of 53 Italian winners.
Scientists from the international XENON collaboration announced today that data from their XENON1T, the world’s most sensitive dark matter experiment, show a surprising excess of events. The scientists do not claim to have found dark matter. Instead, they say to have observed an unexpected rate of events, the source of which is not yet fully understood. The signature of the excess is similar to what might result from a tiny residual amount of tritium (a hydrogen atom with one proton and two neutrons), but could also be a sign of something more exciting—such as the existence of a new particle known as the solar axion or the indication of previously unknown properties of neutrinos.
2019 ends with as many as four researchers from our Section who will soon take on particularly important positions.
Double success in the n_TOF experiment: two Section associates, Alberto Mengoni and Cristian Massimi, were eected respectively Spokesperson and INFN National Manager.
Marco Selvi has been appointed member of the SPS and PS Committee of CERN.
Roberto Spighi is the new Physics Coordinator of the FOOT experiment.
Published Wednesday, January 8, 2020
A small group of cross sections of neutron-induced nuclear reactions are known as “standards” and are known with great precision and accuracy. Standards play a key role in the measurement of neutron-induced cross sections, and in particular in the design of neutron detectors. In experimental measurements, in fact, the cross sections are not determined in absolute terms, but are obtained relative to a standard cross section. For this reason, particular attention is paid to the continuous improvement of the knowledge of the standards (angular distributions of the reaction products, energy region in which these reactions are considered standard) and to the reduction of uncertainties.
At the facility for neutron flight times n_TOF at CERN, the cross sections of the 3 standards 235U (n, f), 6Li (n, 3H) 4He and 10B (n, 4He) were measured for the first time simultaneously 7Li in a wide energy range. The detection apparatus was designed and built by INFN and consists of a stack of solid state detectors and targets of uranium, lithium and boron, placed directly on the neutron beam (as seen in the figure).
As a rule, the results of the precision measurements do not reserve particular surprises, in this case an interesting deviation from the data in the literature was observed for the cross section of 235U (n, f) in the neutron energy range accidents between 10 and 30 keV.
The details of the experiment and the results were published in the European Physical Journal A. The article was selected for the cover of the July issue of EPJ A.
Published Monday, October 14th 2019
Contacts at the INFN Section of Bologna:
Cristian Massimi and Gianni Vannini
The article: https://link.springer.com/content/pdf/10.1140/epja/i2019-12802-7
Two other colleagues from the Division take on new positions
During the DUNE Institutional Board meeting in May,
Laura Patrizii was elected member of the experiment's "Spokesperson Advisory Committee";
Carla Sbarra has become Editor of the prestigious "Journal of Instrumentation" magazine, a point of reference for the community of physicists involved in the development of detectors and electronics for Particle and Astroparticle Physics.
String and Gauge Theories:
String Phenomenology and Exact Results
The ideal candidate is supposed to work in a cross-fertilisation area of string and gauge theories. In more details they should have experience of exact/non-perturbative methodologies in string and gauge theories and/or an expertise in string phenomenology and string cosmology. Preference will be given to candidates with a background which can bridge between these two research activities.