Cargando…

The Gran Sasso muon puzzle

We carry out a time-series analysis of the combined data from three experiments measuring the cosmic muon flux at the Gran Sasso laboratory, at a depth of 3800 m.w.e. These data, taken by the MACRO, LVD and Borexino experiments, span a period of over 20 years, and correspond to muons with a threshol...

Descripción completa

Detalles Bibliográficos
Autores principales: Fernandez-Martinez, Enrique, Mahbubani, Rakhi
Lenguaje:eng
Publicado: 2012
Materias:
Acceso en línea:https://dx.doi.org/10.1088/1475-7516/2012/07/029
http://cds.cern.ch/record/1443567
_version_ 1780924727551852544
author Fernandez-Martinez, Enrique
Mahbubani, Rakhi
author_facet Fernandez-Martinez, Enrique
Mahbubani, Rakhi
author_sort Fernandez-Martinez, Enrique
collection CERN
description We carry out a time-series analysis of the combined data from three experiments measuring the cosmic muon flux at the Gran Sasso laboratory, at a depth of 3800 m.w.e. These data, taken by the MACRO, LVD and Borexino experiments, span a period of over 20 years, and correspond to muons with a threshold energy, at sea level, of around 1.3 TeV. We compare the best-fit period and phase of the full muon data set with the combined DAMA/NaI and DAMA/LIBRA data, which spans the same time period, as a test of the hypothesis that the cosmic ray muon flux is responsible for the annual modulation detected by DAMA. We find in the muon data a large-amplitude fluctuation with a period of around one year, and a phase that is incompatible with that of the DAMA modulation at 5.2 sigmas. Aside from this annual variation, the muon data also contains a further significant modulation with a period between 10 and 11 years and a power well above the 99.9% C.L threshold for noise, whose phase corresponds well with the solar cycle: a surprising observation for such high energy muons. We see no corresponding long-period oscillation in the stratospheric temperature data.
id cern-1443567
institution Organización Europea para la Investigación Nuclear
language eng
publishDate 2012
record_format invenio
spelling cern-14435672023-03-14T16:37:02Zdoi:10.1088/1475-7516/2012/07/029http://cds.cern.ch/record/1443567engFernandez-Martinez, EnriqueMahbubani, RakhiThe Gran Sasso muon puzzleAstrophysics and AstronomyWe carry out a time-series analysis of the combined data from three experiments measuring the cosmic muon flux at the Gran Sasso laboratory, at a depth of 3800 m.w.e. These data, taken by the MACRO, LVD and Borexino experiments, span a period of over 20 years, and correspond to muons with a threshold energy, at sea level, of around 1.3 TeV. We compare the best-fit period and phase of the full muon data set with the combined DAMA/NaI and DAMA/LIBRA data, which spans the same time period, as a test of the hypothesis that the cosmic ray muon flux is responsible for the annual modulation detected by DAMA. We find in the muon data a large-amplitude fluctuation with a period of around one year, and a phase that is incompatible with that of the DAMA modulation at 5.2 sigmas. Aside from this annual variation, the muon data also contains a further significant modulation with a period between 10 and 11 years and a power well above the 99.9% C.L threshold for noise, whose phase corresponds well with the solar cycle: a surprising observation for such high energy muons. We see no corresponding long-period oscillation in the stratospheric temperature data.We carry out a time-series analysis of the combined data from three experiments measuring the cosmic muon flux at the Gran Sasso laboratory, at a depth of 3800 m.w.e. These data, taken by the MACRO, LVD and Borexino experiments, span a period of over 20 years, and correspond to muons with a threshold energy, at sea level, of around 1.3 TeV. We compare the best-fit period and phase of the full muon data set with the combined DAMA/NaI and DAMA/LIBRA data, which spans the same time period, as a test of the hypothesis that the cosmic ray muon flux is responsible for the annual modulation detected by DAMA. We find in the muon data a large-amplitude fluctuation with a period of around one year, and a phase that is incompatible with that of the DAMA modulation at 5.2 sigmas. Aside from this annual variation, the muon data also contains a further significant modulation with a period between 10 and 11 years and a power well above the 99.9% C.L threshold for noise, whose phase corresponds well with the solar cycle: a surprising observation for such high energy muons. We see no corresponding long-period oscillation in the stratospheric temperature data.arXiv:1204.5180CERN-PH-TH-2012-096CERN-PH-TH-2012-096oai:cds.cern.ch:14435672012-04-25
spellingShingle Astrophysics and Astronomy
Fernandez-Martinez, Enrique
Mahbubani, Rakhi
The Gran Sasso muon puzzle
title The Gran Sasso muon puzzle
title_full The Gran Sasso muon puzzle
title_fullStr The Gran Sasso muon puzzle
title_full_unstemmed The Gran Sasso muon puzzle
title_short The Gran Sasso muon puzzle
title_sort gran sasso muon puzzle
topic Astrophysics and Astronomy
url https://dx.doi.org/10.1088/1475-7516/2012/07/029
http://cds.cern.ch/record/1443567
work_keys_str_mv AT fernandezmartinezenrique thegransassomuonpuzzle
AT mahbubanirakhi thegransassomuonpuzzle
AT fernandezmartinezenrique gransassomuonpuzzle
AT mahbubanirakhi gransassomuonpuzzle