Records |
Author |
Zago, L. et al; Gadea, A.; Algora, A. |
Title |
High-spin states in Po-212 above the alpha-decaying (18(+)) isomer |
Type |
Journal Article |
Year |
2022 |
Publication |
Physics Letters B |
Abbreviated Journal |
Phys. Lett. B |
Volume |
834 |
Issue |
|
Pages |
137457 - 5pp |
Keywords |
gamma spectroscopy; Isomer spectroscopy; High-spin spectroscopy |
Abstract |
The nucleus Po-212 has been produced through the fragmentation of a U-238 primary beam at 1GeV/nucleon at GSI, separated with the FRagment Separator, FRS, and studied via isomer gamma-decay spectroscopy with the RISING setup. Two delayed previously unknown gamma rays have been observed. One has been attributed to the E3 decay of a 21(-) isomeric state feeding the alpha-emitting 45-s (18(+)) high-spin isomer. The other gamma-ray line has been assigned to the decay of a higher-lying 23(+) metastable state. These are the first observations of high-spin states above the Po-212 (18(+)) isomer, by virtue of the selectivity obtained via ion-by-ion identification of U-238 fragmentation products. Comparison with shell-model calculations points to shortfalls in the nuclear interactions involving high- jproton and neutron orbitals, to which the region around Z similar to 100 is sensitive. |
Address |
[Zago, L.; Lunardi, S.; Lenzi, S. M.; Mengoni, D.] Univ Padua, Dipartimento Fis, I-35131 Padua, Italy, Email: luca.zago@lnl.infn.it |
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Thesis |
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Publisher ![sorted by Publisher field, descending order (down)](img/sort_desc.gif) |
Elsevier |
Place of Publication |
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Editor |
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Language |
English |
Summary Language |
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Original Title |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0370-2693 |
ISBN |
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Medium |
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Area |
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Expedition |
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Conference |
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Notes |
WOS:000890050000015 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
5457 |
Permanent link to this record |
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Author |
Abdalla, E. et al; Mena, O. |
Title |
Cosmology intertwined: A review of the particle physics, astrophysics, and cosmology associated with the cosmological tensions and anomalies |
Type |
Journal Article |
Year |
2022 |
Publication |
Journal of High Energy Astrophysics |
Abbreviated Journal |
J. High Energy Astrophys. |
Volume |
34 |
Issue |
|
Pages |
49-211 |
Keywords |
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Abstract |
The standard Lambda Cold Dark Matter (Lambda CDM) cosmological model provides a good description of a wide range of astrophysical and cosmological data. However, there are a few big open questions that make the standard model look like an approximation to a more realistic scenario yet to be found. In this paper, we list a few important goals that need to be addressed in the next decade, taking into account the current discordances between the different cosmological probes, such as the disagreement in the value of the Hubble constant H-0, the sigma(8)-S-8 tension, and other less statistically significant anomalies. While these discordances can still be in part the result of systematic errors, their persistence after several years of accurate analysis strongly hints at cracks in the standard cosmological scenario and the necessity for new physics or generalisations beyond the standard model. In this paper, we focus on the 5.0 sigma tension between the Planck CMB estimate of the Hubble constant H-0 and the SH0ES collaboration measurements. After showing the H-0 evaluations made from different teams using different methods and geometric calibrations, we list a few interesting new physics models that could alleviate this tension and discuss how the next decade's experiments will be crucial. Moreover, we focus on the tension of the Planck CMB data with weak lensing measurements and redshift surveys, about the value of the matter energy density Omega(m), and the amplitude or rate of the growth of structure (sigma(8), f sigma(8)). We list a few interesting models proposed for alleviating this tension, and we discuss the importance of trying to fit a full array of data with a single model and not just one parameter at a time. Additionally, we present a wide range of other less discussed anomalies at a statistical significance level lower than the H-0-S-8 tensions which may also constitute hints towards new physics, and we discuss possible generic theoretical approaches that can collectively explain the non-standard nature of these signals. Finally, we give an overview of upgraded experiments and next-generation space missions and facilities on Earth that will be of crucial importance to address all these open questions. |
Address |
[Abdalla, Elcio] Univ Sao Paulo, Inst Fis, CP 66318, BR-0531597 Sao Paulo, Brazil, Email: e.divalentino@sheffield.ac.uk |
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Publisher ![sorted by Publisher field, descending order (down)](img/sort_desc.gif) |
Elsevier |
Place of Publication |
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Editor |
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Language |
English |
Summary Language |
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Original Title |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2214-4048 |
ISBN |
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Medium |
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Area |
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Expedition |
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Conference |
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Notes |
WOS:000807122400002 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
5465 |
Permanent link to this record |
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Author |
Sanchis-Lozano, M.A.; Melia, F.; Lopez-Corredoira, M.; Sanchis-Gual, N. |
Title |
Missing large-angle correlations versus even-odd point-parity imbalance in the cosmic microwave background |
Type |
Journal Article |
Year |
2022 |
Publication |
Astronomy & Astrophysics |
Abbreviated Journal |
Astron. Astrophys. |
Volume |
660 |
Issue |
|
Pages |
A121 - 10pp |
Keywords |
cosmological parameters; cosmic background radiation; cosmology: observations; cosmology: theory; inflation; large-scale structure of Universe |
Abstract |
Context. The existence of a maximum correlation angle (theta(max) & 60 greater than or similar to degrees) in the two-point angular temperature correlations of cosmic microwave background (CMB) radiation, measured by WMAP and Planck, stands in sharp contrast to the prediction of standard inflationary cosmology, in which the correlations should extend across the full sky (i.e., 180 degrees). The introduction of a hard lower cuto ff (k(min)) in the primordial power spectrum, however, leads naturally to the existence of theta(max). Among other cosmological anomalies detected in these data, an apparent dominance of odd-over-even parity multipoles has been seen in the angular power spectrum of the CMB. This feature, however, may simply be due to observational contamination in certain regions of the sky. Aims. In attempting to provide a more detailed assessment of whether this odd-over-even asymmetry is intrinsic to the CMB, we therefore proceed in this paper, first, to examine whether this odd-even parity imbalance also manifests itself in the angular correlation function and, second, to examine in detail the interplay between the presence of theta(max) and this observed anomaly. Methods. We employed several parity statistics and recalculated the angular correlation function for di fferent values of the cuto ff kmin in order to optimize the fit to the di fferent Planck 2018 data. Results. We find a phenomenological connection between these features in the data, concluding that both must be considered together in order to optimize the theoretical fit to the Planck 2018 data. Conclusions. This outcome is independent of whether the parity imbalance is intrinsic to the CMB, but if it is, the odd-over-even asymmetry would clearly point to the emergence of new physics. |
Address |
[Sanchis-Lozano, M-A] Ctr Mixto Univ Valencia, Inst Fis Corpuscular IFIC, CSIC, Dr Moliner 50, Burjassot, Spain, Email: Miguel.Angel.Sanchis@ific.uv.es; |
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Publisher ![sorted by Publisher field, descending order (down)](img/sort_desc.gif) |
Edp Sciences S A |
Place of Publication |
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Language |
English |
Summary Language |
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Original Title |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0004-6361 |
ISBN |
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Medium |
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Area |
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Expedition |
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Conference |
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Notes |
WOS:000786712000002 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
5211 |
Permanent link to this record |
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Author |
Stoppa, F.; Vreeswijk, P.; Bloemen, S.; Bhattacharyya, S.; Caron, S.; Johannesson, G.; Ruiz de Austri, R.; van den Oetelaar, C.; Zaharijas, G.; Groot, P.J.; Cator, E.; Nelemans, G. |
Title |
AutoSourceID-Light Fast optical source localization via U-Net and Laplacian of Gaussian |
Type |
Journal Article |
Year |
2022 |
Publication |
Astronomy & Astrophysics |
Abbreviated Journal |
Astron. Astrophys. |
Volume |
662 |
Issue |
|
Pages |
A109 - 8pp |
Keywords |
astronomical databases; miscellaneous; methods; data analysis; stars; imaging; techniques; image processing |
Abstract |
Aims. With the ever-increasing survey speed of optical wide-field telescopes and the importance of discovering transients when they are still young, rapid and reliable source localization is paramount. We present AutoSourceID-Light (ASID-L), an innovative framework that uses computer vision techniques that can naturally deal with large amounts of data and rapidly localize sources in optical images. Methods. We show that the ASID-L algorithm based on U-shaped networks and enhanced with a Laplacian of Gaussian filter provides outstanding performance in the localization of sources. A U-Net network discerns the sources in the images from many different artifacts and passes the result to a Laplacian of Gaussian filter that then estimates the exact location. Results. Using ASID-L on the optical images of the MeerLICHT telescope demonstrates the great speed and localization power of the method. We compare the results with SExtractor and show that our method outperforms this more widely used method. ASID-L rapidly detects more sources not only in low- and mid-density fields, but particularly in areas with more than 150 sources per square arcminute. The training set and code used in this paper are publicly available. |
Address |
[Stoppa, F.; Vreeswijk, P.; Bloemen, S.; Groot, P. J.; Nelemans, G.] Radboud Univ Nijmegen, Dept Astrophys, IMAPP, POB 9010, NL-6500 GL Nijmegen, Netherlands, Email: f.stoppa@astro.ru.nl |
Corporate Author |
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Thesis |
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Publisher ![sorted by Publisher field, descending order (down)](img/sort_desc.gif) |
Edp Sciences S A |
Place of Publication |
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Editor |
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Language |
English |
Summary Language |
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Original Title |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0004-6361 |
ISBN |
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Medium |
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Area |
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Expedition |
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Conference |
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Notes |
WOS:000818665600009 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
5291 |
Permanent link to this record |
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Author |
HAWC Collaboration (Alfaro, R. et al); Salesa Greus, F. |
Title |
Validation of standardized data formats and tools for ground-level particle-based gamma-ray observatories |
Type |
Journal Article |
Year |
2022 |
Publication |
Astronomy & Astrophysics |
Abbreviated Journal |
Astron. Astrophys. |
Volume |
667 |
Issue |
|
Pages |
A36 - 12pp |
Keywords |
methods; data analysis; gamma rays; general |
Abstract |
Context. Ground-based gamma-ray astronomy is still a rather young field of research, with strong historical connections to particle physics. This is why most observations are conducted by experiments with proprietary data and analysis software, as is usual in the particle physics field. However, in recent years, this paradigm has been slowly shifting toward the development and use of open-source data formats and tools, driven by upcoming observatories such as the Cherenkov Telescope Array (CTA). In this context, a community-driven, shared data format (the gamma-astro-data-format, or GADF) and analysis tools such as Gammapy and ctools have been developed. So far, these efforts have been led by the Imaging Atmospheric Cherenkov Telescope community, leaving out other types of ground-based gamma-ray instruments. Aims. We aim to show that the data from ground particle arrays, such as the High-Altitude Water Cherenkov (HAWC) observatory, are also compatible with the GADF and can thus be fully analyzed using the related tools, in this case, Gammapy. Methods. We reproduced several published HAWC results using Gammapy and data products compliant with GADF standard. We also illustrate the capabilities of the shared format and tools by producing a joint fit of the Crab spectrum including data from six different gamma-ray experiments. Results. We find excellent agreement with the reference results, a powerful confirmation of both the published results and the tools involved. Conclusions. The data from particle detector arrays such as the HAWC observatory can be adapted to the GADF and thus analyzed with Gammapy. A common data format and shared analysis tools allow multi-instrument joint analysis and effective data sharing. To emphasize this, a sample of Crab nebula event lists is made public with this paper. Because of the complementary nature of pointing and wide-field instruments, this synergy will be distinctly beneficial for the joint scientific exploitation of future observatories such as the Southern Wide-field Gamma-ray Observatory and CTA. |
Address |
[Albert, A.; Durocher, M.; Harding, J. P.] Los Alamos Natl Lab, Phys Div, Los Alamos, NM USA, Email: laura.olivera-nieto@mpi-hd.mpg.de |
Corporate Author |
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Thesis |
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Publisher ![sorted by Publisher field, descending order (down)](img/sort_desc.gif) |
Edp Sciences S A |
Place of Publication |
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Editor |
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Language |
English |
Summary Language |
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Original Title |
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Series Editor |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0004-6361 |
ISBN |
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Area |
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Expedition |
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Conference |
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Notes |
WOS:000879223700008 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
5408 |
Permanent link to this record |