After the completion of the gallium solar neutrino experiments at the Laboratori Nazionali del Gran Sasso (Gallex: 1991–1997; GNO: 1998–2003) we have retrospectively updated the Gallex results with ...the help of new technical data that were impossible to acquire for principle reasons before the completion of the low rate measurement phase (that is, before the end of the GNO solar runs). Subsequent high rate experiments have allowed the calibration of absolute internal counter efficiencies and of an advanced pulse shape analysis for counter background discrimination. The updated overall result for Gallex (only) is 73.4−7.3+7.1 SNU. This is 5.3% below the old value of 77.5−7.8+7.5 SNU (Gallex Collaboration, W. Hampel et al., 1999 1), with a substantially reduced error. A similar reduction is obtained from the reanalysis of the 51Cr neutrino source experiments of 1994/1995.
We report the complete GNO solar neutrino results for the measuring periods GNO III, GNO II, and GNO I. The result for GNO III (last 15 solar runs) is 54.3−9.3+9.9(stat)±2.3(syst)SNU(1σ) or ...54.3−9.6+10.2(incl. syst) SNU (1σ) with errors combined. The GNO experiment is now terminated after altogether 58 solar exposure runs that were performed between 20 May 1998 and 9 April 2003. The combined result for GNO (I+II+III) is 62.9−5.3+5.5(stat)±2.5(syst) SNU (1σ) or 62.9−5.9+6.0 SNU (1σ) with errors combined in quadrature. Overall, gallium based solar observations at LNGS (first in GALLEX, later in GNO) lasted from 14 May 1991 through 9 April 2003. The joint result from 123 runs in GNO and GALLEX is 69.3±5.5(incl. syst) SNU (1σ). The distribution of the individual run results is consistent with the hypothesis of a neutrino flux that is constant in time. Implications from the data in particle- and astrophysics are reiterated.
We report the GALLEX solar neutrino results for the measuring period GALLEX IV, from 14 February 1996 until 23 January 1997. Counting for the GALLEX IV runs was completed on 19 June 1997. The GALLEX ...IV result from 12 solar runs is 118.4 ± 17.8 (stat.) ± 6.6 (sys.) SNU (1
σ). The combined result for GALLEX I+II+III+IV, which comprises 65 solar runs, is 77.5 ± 6.2
+4.3
−4.7(1
σ) SNU. The GALLEX experimental program to register solar neutrinos has now been completed. In April 1998, GALLEX was succeeded by a new project, the Gallium Neutrino Observatory (GNO), with newly defined motives and goals.
We report the first GNO solar neutrino results for the measuring period GNO I, solar exposure time May 20, 1998 till January 12, 2000. In the present analysis, counting results for solar runs ...SR1–SR19 were used till April 4, 2000. With counting completed for all but the last 3 runs (SR17–SR19), the GNO I result is 65.8 ±
10.2
9.6 (stat.) ±
3.4
3.6 (syst.) SNU (1
σ) or 65.8 ±
10.7
10.2 (incl. syst.) SNU (1
σ) with errors combined. This may be compared to the result for Gallex (I–IV), which is 77.5 ±
7.6
7.8 (incl. syst.) SNU (1
σ). A combined result from both GNO I and Gallex (I–IV) together is 74.1 ±
6.7
6.8 (incl. syst.) SNU (1
σ).
The GALLEX solar neutrino experiment as well as the follow-up experiment GNO are low-level, low-statistics experiments with a mean production rate of 0.7 71Ge atoms per day by neutrino capture on ...30.3t of natural gallium. This is a challenge with respect to the long time stability of the whole equipment, especially the stability of the electronic components which acquire the signals of the 71Ge decay events in proportional counters. Approximately, every month a sample of about ten 71Ge atoms (half-life 11.4d) is typically measured in the GALLEX and GNO experiments for a period of half a year. The background is minimized by low-level techniques. In addition, 71Ge decays are distinguished from background events by pulse shape analyses. The background rejection efficiency is directly correlated with the signal to noise ratio of the recorded events. A method is described which increases the signal to noise ratio of the acquired ionization events and allows to distinguish between detector signals and noise picked up from the detector environment. This method can be applied not only for proportional counters but also for many other detectors.
Detector for 222Rn measurements in air at the 1mBq/m3 level Kiko, J.
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
3/2001, Volume:
460, Issue:
2-3
Journal Article
We report the GALLEX solar neutrino results for the measuring period GALLEX III, the period from 12 October 1994-4 October 1995. Counting for these runs was completed on 29 March 1996. The GALLEX III ...result (14 runs) is 53.9 ± 10.6(stat.) ± 3.1 (syst.) SNU (1σ). This is 15.8 SNU below but statistically compatible with the new combined result for GALLEX (I+II+III) (53 runs), which is 69.7 ± 6.7(stat.)
−4.5
+3.9(syst.) SNU (1σ) or (69.7
−8.1
+7.8) SNU with errors quadratically added. We also give the preliminary result from our second
51Cr-source experiment: the measured detector response is 83±10% of expectation. The combined result from both GALLEX
51Cr-source experiments is 92±8% of expectation.
The Borexino detector at the Laboratori Nazionali del Gran Sasso Back, H.; Balata, M.; de Bellefon, A. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
03/2009, Volume:
600, Issue:
3
Journal Article
Peer reviewed
Open access
Borexino, a large volume detector for low energy neutrino spectroscopy, is currently running underground at the Laboratori Nazionali del Gran Sasso, Italy. The main goal of the experiment is the ...real-time measurement of sub-MeV solar neutrinos, and particularly of the monoenergetic (862
keV)
7Be electron capture neutrinos, via neutrino–electron scattering in an ultra-pure liquid scintillator. This paper is mostly devoted to the description of the detector structure, the photomultipliers, the electronics, and the trigger and calibration systems. The real performance of the detector, which always meets, and sometimes exceeds, design expectations, is also shown. Some important aspects of the Borexino project, i.e. the fluid handling plants, the purification techniques and the filling procedures, are not covered in this paper and are, or will be, published elsewhere (see Introduction and Bibliography).
The Deep South of the U.S. continues to have increased incidence of new cases of HIV since its inception, despite many advancements in HIV testing, treatment, and prevention. According to data by the ...CDC, rates are increasingly high among heterosexual African American (AA) men and women compared to their non-AA counterparts (CDC/HIV, 2017). In 2015, heterosexual transmission accounted for a share of new diagnoses for AA men and is the most common transmission route for AA women (KFF, 2017). The primary population affected by HIV/AIDS in Alabama is men who have sex with men (MSM) at 62.2%, followed by heterosexual males and females at 30.8% (CDC, 2015). However, research among the general population, specifically heterosexual AAs men’s numbers have declined considerably since the mid-1990s. Research has shown that HIV-related stigma significantly impacts people living with HIV (PLWH), (Beaulieu, Adrien, Potvin & Dassa, 2014; Bennett, Hersh, Herres, & Foster, 2016). Yet, little is known about how HIV-related stigma affects this population or their sexual health behavior (risk or preventive) decision making. The present study explored the sexual health risk, HIV prevention, and perceptions of HIV-related stigma of heterosexual, African American men and women in Birmingham, Alabama. Guided by the Theory of Planned Behavior and using Venue-based sampling, the study recruited 134 participants at local grocery stores, retail shops, and libraries. Participants completed a one-time survey instrument, in addition to being provided to HIV and PrEP education materials and resources to access services. Further guided by three aims and four research questions regarding the relationship of sexual health risk with HIV prevention and HIV-related stigma, the study identified several areas of sexual health risk within this population where additional work is needed based on participant responses. Additionally, analyses found multiple significant associations between sexual health risk and HIV prevention, even after controlling for relevant demographics. Additionally, there was only one significant association found between HIV-related stigma and HIV prevention variables. Ultimately, the findings of the study suggest a need for additional sexual health and HIV related research involving heterosexual Africa Americans. Specifically, the present study suggests that more needs to be done to address the education and awareness of HIV, sexual health risk, and HIV prevention gaps in this population.
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