Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 115
Filter
1.
Phys Rev Lett ; 131(9): 091801, 2023 Sep 01.
Article in English | MEDLINE | ID: mdl-37721818

ABSTRACT

We measured the nuclear-recoil ionization yield in silicon with a cryogenic phonon-sensitive gram-scale detector. Neutrons from a monoenergetic beam scatter off of the silicon nuclei at angles corresponding to energy depositions from 4 keV down to 100 eV, the lowest energy probed so far. The results show no sign of an ionization production threshold above 100 eV. These results call for further investigation of the ionization yield theory and a comprehensive determination of the detector response function at energies below the keV scale.

2.
Phys Rev Lett ; 127(8): 081802, 2021 Aug 20.
Article in English | MEDLINE | ID: mdl-34477436

ABSTRACT

The Cryogenic Dark Matter Search low ionization threshold experiment (CDMSlite) achieved efficient detection of very small recoil energies in its germanium target, resulting in sensitivity to lightly ionizing particles (LIPs) in a previously unexplored region of charge, mass, and velocity parameter space. We report first direct-detection limits calculated using the optimum interval method on the vertical intensity of cosmogenically produced LIPs with an electric charge smaller than e/(3×10^{5}), as well as the strongest limits for charge ≤e/160, with a minimum vertical intensity of 1.36×10^{-7} cm^{-2} s^{-1} sr^{-1} at charge e/160. These results apply over a wide range of LIP masses (5 MeV/c^{2} to 100 TeV/c^{2}) and cover a wide range of ßγ values (0.1-10^{6}), thus excluding nonrelativistic LIPs with ßγ as small as 0.1 for the first time.

3.
Phys Rev Lett ; 127(6): 061801, 2021 Aug 06.
Article in English | MEDLINE | ID: mdl-34420312

ABSTRACT

We present limits on spin-independent dark matter-nucleon interactions using a 10.6 g Si athermal phonon detector with a baseline energy resolution of σ_{E}=3.86±0.04(stat)_{-0.00}^{+0.19}(syst) eV. This exclusion analysis sets the most stringent dark matter-nucleon scattering cross-section limits achieved by a cryogenic detector for dark matter particle masses from 93 to 140 MeV/c^{2}, with a raw exposure of 9.9 g d acquired at an above-ground facility. This work illustrates the scientific potential of detectors with athermal phonon sensors with eV-scale energy resolution for future dark matter searches.

5.
Phys Rev Lett ; 120(6): 061802, 2018 Feb 09.
Article in English | MEDLINE | ID: mdl-29481237

ABSTRACT

We report the result of a blinded search for weakly interacting massive particles (WIMPs) using the majority of the SuperCDMS Soudan data set. With an exposure of 1690 kg d, a single candidate event is observed, consistent with expected backgrounds. This analysis (combined with previous Ge results) sets an upper limit on the spin-independent WIMP-nucleon cross section of 1.4×10^{-44} (1.0×10^{-44}) cm^{2} at 46 GeV/c^{2}. These results set the strongest limits for WIMP-germanium-nucleus interactions for masses >12 GeV/c^{2}.

6.
Phys Rev Lett ; 121(5): 051301, 2018 Aug 03.
Article in English | MEDLINE | ID: mdl-30118251

ABSTRACT

We present the first limits on inelastic electron-scattering dark matter and dark photon absorption using a prototype SuperCDMS detector having a charge resolution of 0.1 electron-hole pairs (CDMS HVeV, a 0.93 g CDMS high-voltage device). These electron-recoil limits significantly improve experimental constraints on dark matter particles with masses as low as 1 MeV/c^{2}. We demonstrate a sensitivity to dark photons competitive with other leading approaches but using substantially less exposure (0.49 g d). These results demonstrate the scientific potential of phonon-mediated semiconductor detectors that are sensitive to single electronic excitations.

7.
Phys Rev Lett ; 116(7): 071301, 2016 Feb 19.
Article in English | MEDLINE | ID: mdl-26943526

ABSTRACT

The CDMS low ionization threshold experiment (CDMSlite) uses cryogenic germanium detectors operated at a relatively high bias voltage to amplify the phonon signal in the search for weakly interacting massive particles (WIMPs). Results are presented from the second CDMSlite run with an exposure of 70 kg day, which reached an energy threshold for electron recoils as low as 56 eV. A fiducialization cut reduces backgrounds below those previously reported by CDMSlite. New parameter space for the WIMP-nucleon spin-independent cross section is excluded for WIMP masses between 1.6 and 5.5 GeV/c^{2}.

8.
Phys Rev Lett ; 114(11): 111302, 2015 Mar 20.
Article in English | MEDLINE | ID: mdl-25839256

ABSTRACT

While the standard model of particle physics does not include free particles with fractional charge, experimental searches have not ruled out their existence. We report results from the Cryogenic Dark Matter Search (CDMS II) experiment that give the first direct-detection limits for cosmogenically produced relativistic particles with electric charge lower than e/6. A search for tracks in the six stacked detectors of each of two of the CDMS II towers finds no candidates, thereby excluding new parameter space for particles with electric charges between e/6 and e/200.

9.
Phys Rev Lett ; 112(24): 241302, 2014 Jun 20.
Article in English | MEDLINE | ID: mdl-24996080

ABSTRACT

We report a first search for weakly interacting massive particles (WIMPs) using the background rejection capabilities of SuperCDMS. An exposure of 577 kg days was analyzed for WIMPs with mass <30 GeV/c(2), with the signal region blinded. Eleven events were observed after unblinding. We set an upper limit on the spin-independent WIMP-nucleon cross section of 1.2×10(-42) cm(2) at 8 GeV/c(2). This result is in tension with WIMP interpretations of recent experiments and probes new parameter space for WIMP-nucleon scattering for WIMP masses <6 GeV/c(2).

10.
Phys Rev Lett ; 112(4): 041302, 2014 Jan 31.
Article in English | MEDLINE | ID: mdl-24580434

ABSTRACT

SuperCDMS is an experiment designed to directly detect weakly interacting massive particles (WIMPs), a favored candidate for dark matter ubiquitous in the Universe. In this Letter, we present WIMP-search results using a calorimetric technique we call CDMSlite, which relies on voltage-assisted Luke-Neganov amplification of the ionization energy deposited by particle interactions. The data were collected with a single 0.6 kg germanium detector running for ten live days at the Soudan Underground Laboratory. A low energy threshold of 170 eVee (electron equivalent) was obtained, which allows us to constrain new WIMP-nucleon spin-independent parameter space for WIMP masses below 6 GeV/c2.

11.
Phys Rev Lett ; 111(25): 251301, 2013 Dec 20.
Article in English | MEDLINE | ID: mdl-24483735

ABSTRACT

We report results of a search for weakly interacting massive particles (WIMPS) with the silicon detectors of the CDMS II experiment. This blind analysis of 140.2 kg day of data taken between July 2007 and September 2008 revealed three WIMP-candidate events with a surface-event background estimate of 0.41(-0.08)(+0.20)(stat)(-0.24)(+0.28)(syst). Other known backgrounds from neutrons and 206Pb are limited to <0.13 and <0.08 events at the 90% confidence level, respectively. The exposure of this analysis is equivalent to 23.4 kg day for a recoil energy range of 7-100 keV for a WIMP of mass 10 GeV/c2. The probability that the known backgrounds would produce three or more events in the signal region is 5.4%. A profile likelihood ratio test of the three events that includes the measured recoil energies gives a 0.19% probability for the known-background-only hypothesis when tested against the alternative WIMP+background hypothesis. The highest likelihood occurs for a WIMP mass of 8.6 GeV/c2 and WIMP-nucleon cross section of 1.9×10(-41) cm2.

12.
Phys Rev Lett ; 106(13): 131302, 2011 Apr 01.
Article in English | MEDLINE | ID: mdl-21517371

ABSTRACT

We report results from a reanalysis of data from the Cryogenic Dark Matter Search (CDMS II) experiment at the Soudan Underground Laboratory. Data taken between October 2006 and September 2008 using eight germanium detectors are reanalyzed with a lowered, 2 keV recoil-energy threshold, to give increased sensitivity to interactions from weakly interacting massive particles (WIMPs) with masses below ∼10 GeV/c(2). This analysis provides stronger constraints than previous CDMS II results for WIMP masses below 9 GeV/c(2) and excludes parameter space associated with possible low-mass WIMP signals from the DAMA/LIBRA and CoGeNT experiments.

13.
Phys Rev Lett ; 103(14): 141802, 2009 Oct 02.
Article in English | MEDLINE | ID: mdl-19905561

ABSTRACT

We report on the first axion search results from the Cryogenic Dark Matter Search (CDMS) experiment at the Soudan Underground Laboratory. An energy threshold of 2 keV for electron-recoil events allows a search for possible solar axion conversion into photons or local galactic axion conversion into electrons in the germanium crystal detectors. The solar axion search sets an upper limit on the Primakov coupling g(agammagamma) of 2.4x10(-9) GeV-1 at the 95% confidence level for an axion mass less than 0.1 keV/c2. This limit benefits from the first precise measurement of the absolute crystal plane orientations in this type of experiment. The galactic axion search analysis sets a world-leading experimental upper limit on the axioelectric coupling g(aee) of 1.4x10(-12) at the 90% confidence level for an axion mass of 2.5 keV/c2.

14.
Clin Pharmacol Ther ; 19(3): 310-7, 1976 Mar.
Article in English | MEDLINE | ID: mdl-1083326

ABSTRACT

The effect of marijuana smoking on sheep cell rosetting properties of both early (active) and total T lymphocytes was studied in vitro. Significantly fewer active rosettes were formed by T cells from a population of 35 who appeared to be chronic marijuana smokers than the 34 controls. The late, or cold-enhanced rosettes formed by smokers and nonsmokers were similar, suggesting that similar numbers of rosette-forming T cells were present in the peripheral blood of smokers. These data suggest that marijuana smoking may affect the function of a subpopulation of T lymphocytes, identified by their capacity to form early rosettes, possibly by affecting these cell membranes.


Subject(s)
Cannabis/pharmacology , T-Lymphocytes/drug effects , Adolescent , Adult , Animals , Cells, Cultured , Cold Temperature , Erythrocytes/immunology , Female , Humans , Immune Adherence Reaction , In Vitro Techniques , Leukocyte Count , Male , Sheep , T-Lymphocytes/immunology , Time Factors
15.
Am J Med ; 65(1): 46-52, 1978 Jul.
Article in English | MEDLINE | ID: mdl-686001

ABSTRACT

During an 11 year overview of methadone treatment, 161 (72 per cent) of 225 patients who completed detoxification were followed up to eight years. Fifty-one (22.6 per cent) of those were classified as stable and narcotic free 2.9 years after detoxification. Of 89 self-selected patients who had undergone a planned, supported, "therapeutic" detoxification, 37 (42 per cent) were classified narcotic-free; whereas many fewer were so judged after other methods of detoxification. Relapse to nonprescribed opioid use, detected in 34 (38.7 per cent) of those traced, was inversely related to time since detoxification. Relapse potential was very low after three years of apparent continuous narcotic-free existence; three years should be a minimal time for successful detoxification. Some subjects had several cycles of methadone treatment and detoxification. Most patients with combined alcohol-methadone dependencies did poorly, whether or not detoxification from opioids was undertaken. Since the frequency of enduring narcotic-free state was only 9.7 per cent of 522 patients in the treatment sample, detoxification should not be a realistic goal for all patients who enter treatment.


Subject(s)
Methadone/therapeutic use , Narcotics , Substance-Related Disorders/rehabilitation , Adolescent , Adult , Aged , Alcoholism/complications , Female , Follow-Up Studies , Humans , Male , Middle Aged , New York City , Quality of Life
16.
J Clin Psychiatry ; 50(8): 278-84, 1989 Aug.
Article in English | MEDLINE | ID: mdl-2569456

ABSTRACT

The authors review recent developments in the management of alcohol withdrawal, including its clinical components, available treatment strategies, and some recent neurochemical and endocrine research in the area.


Subject(s)
Ethanol/adverse effects , Substance Withdrawal Syndrome/therapy , Adrenergic beta-Antagonists/therapeutic use , Alcoholism/complications , Anti-Anxiety Agents/therapeutic use , Benzodiazepines , Humans , Substance Withdrawal Syndrome/drug therapy , Substance Withdrawal Syndrome/etiology
17.
Drug Alcohol Depend ; 6(6): 365-71, 1980 Dec.
Article in English | MEDLINE | ID: mdl-6110530

ABSTRACT

Sixty-nine (9.2%) of 750 consecutive persons entering a chemical-dependence treatment hospital had urinary evidence of benzodiazepines, a somewhat higher proportion than in the general adult American population. The 54 subjects in whose urine benzodiazepines, but not the other commonly abused psychoactive drugs, were detected, had varied clinical findings. One had used benzodiazepines only, 38 others were alcoholic benzodiazepine users, and 15 were multiple-drug (including benzodiazepines) users. Of these 54 only 6 (11%) developed major withdrawal symptoms. All 6 had used high doses of benzodiazepines (larger than or equal to 30 mg of diazepam or equivalent) daily. The risk of major withdrawal symptoms was about 50% for the high benzodiazepines--heavy alcohol group and zero for all other benzodiazepine-consuming patients. While clinical vigilance regarding withdrawal is urged for all benzodiazepine consumers, it is especially important amongst alcoholics, consuming high doses of benzodiazepines.


Subject(s)
Alcohol Drinking , Anti-Anxiety Agents , Substance Withdrawal Syndrome/etiology , Substance-Related Disorders , Adult , Anti-Anxiety Agents/urine , Benzodiazepines , Female , Humans , Male
18.
Drug Alcohol Depend ; 8(4): 337-43, 1981 Dec.
Article in English | MEDLINE | ID: mdl-6802625

ABSTRACT

Plasma lipids, including total cholesterol, plasma triglycerides, high density lipoprotein cholesterol and several apolipoproteins were measured in eight otherwise healthy male alcoholics at the beginning and during a 4-week inpatient abstinence treatment program. The initial triglyceride and apolipoprotein A-11 levels were higher and apolipoprotein B was lower in alcoholics than in 12 nondrinking control subjects. During the alcohol abstinence there was a parallel fall in the levels of high density lipoprotein cholesterol, and apolipoproteins A-I and A-II and a rise in apolipoprotein B. The changes in apolipoproteins C-III and E were less consistent. These findings suggest that, even in otherwise healthy alcoholics, elevated levels of apolipoproteins A-I and A-II on admission are ameliorated during abstinence of several weeks.


Subject(s)
Alcoholism/blood , Apolipoproteins C , Apolipoproteins/blood , Adult , Alcoholism/rehabilitation , Apolipoprotein A-I , Apolipoprotein A-II , Apolipoprotein C-III , Apolipoproteins B , Apolipoproteins E , Cholesterol/blood , Humans , Lipoproteins, HDL/blood , Male , Smoking , Triglycerides/blood
19.
Life Sci ; 30(20): 1721-4, 1982 May 17.
Article in English | MEDLINE | ID: mdl-7098769

ABSTRACT

Seven patients entering an alcoholic detoxification and treatment unit exhibited elevated levels of plasma high density lipoprotein cholesterol (HDLC) and enhanced metabolic disposal of antipyrine. Following a 2-week abstinence treatment, the HDLC levels were reduced by 28% (from 64 to 47 mg/100 ml) and the t 1/2 of antipyrine was extended from 12.4 to 13.7 hours. The extent of the HDLC reduction correlated with the antipyrine t 1/2 changes (r = -0.753, P = 0.05).


Subject(s)
Alcoholism/blood , Antipyrine/metabolism , Cholesterol/blood , Lipoproteins, HDL/blood , Adult , Aged , Alcohol Drinking , Cholesterol, HDL , Ethanol/metabolism , Female , Humans , Liver Function Tests , Male , Microsomes, Liver/metabolism , Middle Aged
20.
Am Psychol ; 46(3): 206-19, 1991 Mar.
Article in English | MEDLINE | ID: mdl-2035931

ABSTRACT

Daniel Stern's (1985) respected theory of infant development is critiqued from a social-constructionist perspective in order to demonstrate how decontextualized psychology theories inadvertantly perpetuate the political status quo. Self-invariants in the core-self phase are discussed as reflections of the current configuration of self rather than a discovery of universal elements of human development. The parental attunement response is reinterpreted as a way by which Western interiority and subjectivity are socially constructed. Language as the fundamental cause of alienation and dividedness is disputed. In Stern's theory, universal qualities of the self and the processes of language acquisition are responsible for several psychological ills characteristic of the 20th century. By exonerating political structures as causal factors, decontextualized theories legitimize, justify, and perpetuate current arrangements of power and privilege.


Subject(s)
Ego , Politics , Psychological Theory , Psychology, Child , Cultural Characteristics , Humans , Infant , Interpersonal Relations , Social Environment
SELECTION OF CITATIONS
SEARCH DETAIL