ABSTRACT
We report on the electrostatic trapping of neutral SrF molecules. The molecules are captured from a cryogenic buffer-gas beam source into the moving traps of a 4.5-m-long traveling-wave Stark decelerator. The SrF molecules in X^{2}Σ^{+}(v=0,N=1) state are brought to rest as the velocity of the moving traps is gradually reduced from 190 m/s to zero. The molecules are held for up to 50 ms in multiple electric traps of the decelerator. The trapped packets have a volume (FWHM) of 1 mm^{3} and a velocity spread of 5(1) m/s, which corresponds to a temperature of 60(20) mK. Our result demonstrates a factor 3 increase in the molecular mass that has been Stark decelerated and trapped. Heavy molecules (mass>100 amu) offer a highly increased sensitivity to probe physics beyond the standard model. This work significantly extends the species of neutral molecules of which slow beams can be created for collision studies, precision measurement, and trapping experiments.
ABSTRACT
A supersonic beam source for SrF and BaF molecules is constructed by combining the expansion of carrier gas (a mixture of 2% SF6 and 98% argon) from an Even-Lavie valve with laser ablation of a barium/strontium metal target at a repetition rate of 10 Hz. Molecular beams with a narrow translational velocity spread are produced at relative values of Δv/v = 0.053(11) and 0.054(9) for SrF and BaF, respectively. The relative velocity spread of the beams produced in our source is lower in comparison with the results from other metal fluoride beams produced in supersonic laser ablation sources. The rotational temperature of BaF is measured to be 3.5 K. The source produces 6 × 108 and 107 molecules per steradian per pulse in the X2Σ+ (ν = 0, N = 1) state of BaF and SrF molecules, respectively, a state amenable to Stark deceleration and laser cooling.
ABSTRACT
Recently the spin-lattice relaxation time T1 of hyperpolarized (HP)-(129)Xe was significantly improved by using uncoated and Rb-free storage vessels of GE180 glass. For these cells, a simple procedure was established to obtain reproducible wall relaxation times of about 18 h. Then the limiting relaxation mechanism in pure Xe is due to the coupling between the nuclear spins and the angular momentum of the Xe-Xe van-der-Waals-molecules. This mechanism can be significantly reduced by using different buffer gases of which CO2 was discovered to be the most efficient so far. From these values, it was estimated that for a 1:1 mixture of HP-Xe with CO2 a longitudinal relaxation time of about 7 h can be expected, sufficient to transport HP-Xe from a production to a remote application site. This prediction was verified for such a mixture at a total pressure of about 1 bar in a 10 cm glass cell showing a storage time of T1≈9 h (for T1(wall)=(34±9) h) which was transported inside a magnetic box over a distance of about 200 km by car.
ABSTRACT
Results of optical frequency transfer over a carrier-grade dense-wavelength-division-multiplexing (DWDM) optical fiber network are presented. The relation between soil temperature changes on a buried optical fiber and frequency changes of an optical carrier through the fiber is modeled. Soil temperatures, measured at various depths by the Royal Netherlands Meteorology Institute (KNMI) are compared with observed frequency variations through this model. A comparison of a nine-day record of optical frequency measurements through the 2×298 km fiber link with soil temperature data shows qualitative agreement. A soil temperature model is used to predict the link stability over longer periods (days-months-years). We show that optical frequency dissemination is sufficiently stable to distribute and compare, e.g., rubidium frequency standards over standard DWDM optical fiber networks using unidirectional fibers.
ABSTRACT
A measurement of the final state distribution of the (8)B ß decay, obtained by implanting a (8)B beam in a double-sided silicon strip detector, is reported here. The present spectrum is consistent with a recent independent precise measurement performed by our collaboration at the IGISOL facility, Jyväskylä [O. S. Kirsebom et al., Phys. Rev. C 83, 065802 (2011)]. It shows discrepancies with previously measured spectra, leading to differences in the derived neutrino spectrum. Thanks to a low detection threshold, the neutrino spectrum is for the first time directly extracted from the measured final state distribution, thus avoiding the uncertainties related to the extrapolation of R-matrix fits. Combined with the IGISOL data, this leads to an improvement of the overall errors and the extension of the neutrino spectrum at high energy. The new unperturbed neutrino spectrum represents a benchmark for future measurements of the solar neutrino flux as a function of energy.
ABSTRACT
The spin precession frequency of muons stored in the (g-2) storage ring has been analyzed for evidence of Lorentz and CPT violation. Two Lorentz and CPT violation signatures were searched for a nonzero delta omega a(=omega a mu+ - omega a mu-) and a sidereal variation of omega a mu+/-). No significant effect is found, and the following limits on the standard-model extension parameters are obtained: bZ = -(1.0+/-1.1) x 10(-23) GeV; (m mu dZ0 + HXY)=(1.8+/-6.0) x 10(-23) GeV; and the 95% confidence level limits b perpendicular mu+ <1.4 x 10(-24) GeV and b perpendicular mu- <2.6 x 10(-24) GeV.
ABSTRACT
A new highly sensitive method of looking for electric dipole moments of charged particles in storage rings is described. The major systematic errors inherent in the method are addressed and ways to minimize them are suggested. It seems possible to measure the muon EDM to levels that test speculative theories beyond the standard model.
ABSTRACT
The anomalous magnetic moment of the negative muon has been measured to a precision of 0.7 ppm (ppm) at the Brookhaven Alternating Gradient Synchrotron. This result is based on data collected in 2001, and is over an order of magnitude more precise than the previous measurement for the negative muon. The result a(mu(-))=11 659 214(8)(3) x 10(-10) (0.7 ppm), where the first uncertainty is statistical and the second is systematic, is consistent with previous measurements of the anomaly for the positive and the negative muon. The average of the measurements of the muon anomaly is a(mu)(exp)=11 659 208(6) x 10(-10) (0.5 ppm).
ABSTRACT
A higher precision measurement of the anomalous g value, a(mu)=(g-2)/2, for the positive muon has been made at the Brookhaven Alternating Gradient Synchrotron, based on data collected in the year 2000. The result a(mu(+))=11 659 204(7)(5)x10(-10) (0.7 ppm) is in good agreement with previous measurements and has an error about one-half that of the combined previous data. The present world average experimental value is a(mu)(expt)=11 659 203(8)x10(-10) (0.7 ppm).
ABSTRACT
Following a suggestion from Kostelecký et al., we evaluated a test of CPT and Lorentz invariance from the microwave spectroscopy of muonium. Hamiltonian terms beyond the standard model violating CPT and Lorentz invariance would contribute frequency shifts deltanu(12) and deltanu(34) to nu(12) and nu(34), the two transitions involving muon spin flip, which were precisely measured in ground state muonium in a strong magnetic field of 1.7 T. The shifts would be indicated by anticorrelated oscillations in nu(12) and nu(34) at the Earth's sidereal frequency. No time dependence was found in nu(12) or nu(34) at the level of 20 Hz, limiting the size of some CPT and Lorentz-violating parameters at the level of 2x10(-23) GeV.
ABSTRACT
A precise measurement of the anomalous g value, a(mu) = (g-2)/2, for the positive muon has been made at the Brookhaven Alternating Gradient Synchrotron. The result a(mu+) = 11 659 202(14) (6) x 10(-10) (1.3 ppm) is in good agreement with previous measurements and has an error one third that of the combined previous data. The current theoretical value from the standard model is a(mu)(SM) = 11 659 159.6(6.7) x 10(-10) (0.57 ppm) and a(mu)(exp) - a(mu)(SM) = 43(16) x 10(-10) in which a(mu)(exp) is the world average experimental value.
ABSTRACT
Fifty-five hospital-treated patients with the ICD-10 diagnosis of 'recurrent depressive episode(s)' were classified according to the Newcastle Depressive Diagnostic Scale as having either psychogenic (n = 25) or endogenous (n = 30) depression and interviewed using several inventories on personality and psychopathology (Composite International Diagnostic Interview, Symptom Check List, Inventory of Interpersonal Problems, IIP, NEO Five-Factor Personality Inventory, Social Adjustment Scale, Questionnaire of the Motivation to Seek Psychotherapy). Except for the IIP, individual subscales disclosed significant differences between the two groups. In light of these results, the grouping of these two disorders into one diagnostic group in the ICD-10 is critically discussed.
Subject(s)
Mood Disorders/classification , Mood Disorders/diagnosis , Psychiatric Status Rating Scales , Depressive Disorder/diagnosis , Depressive Disorder/etiology , Depressive Disorder/therapy , Diagnosis, Differential , Female , Humans , Interpersonal Relations , Male , Middle Aged , Patient Acceptance of Health Care , Personality , Personality Inventory , Psychotherapy , Reproducibility of Results , Severity of Illness Index , Social AdjustmentABSTRACT
The 1s-2s interval has been measured in the muonium (&mgr;(+)e(-)) atom by Doppler-free two-photon pulsed laser spectroscopy. The frequency separation of the states was determined to be 2 455 528 941.0(9.8) MHz, in good agreement with quantum electrodynamics. The result may be interpreted as a measurement of the muon-electron charge ratio as -1-1.1(2.1)x10(-9). We expect significantly higher accuracy at future high flux muon sources and from cw laser technology.
ABSTRACT
BACKGROUND: Impaired movement of the cricoarytenoid joint with hoarseness and immobility of the vocal ligament may occur as a consequence of laryngeal trauma and joint disease. Little is known to date about the cricoarytenoid joint capsule and its role in joint pathology. METHODS: The present study analyses the structure of the cricoarytenoid joint capsule by means of histological, immunohistochemical, and scanning electron microscopical methods. Investigations are performed on larynges of 17 male and 16 female. RESULTS: The cricoarytenoid joint was found to be lined by a wide and lax joint capsule consisting of a fibrous and a synovial membrane. The capsule was strengthened posteriorly by the cricoarytenoid ligament. As like the fibrous membrane the cricoarytenoid ligament consisted mainly of collagen types I and III. Moreover the ligament was found to be rich in elastic fibers. Unexpected large and intensively vascularized synovial folds projected into the joint cavity. CONCLUSION: The capsule of the cricoarytenoid joint can be compared with the joint capsules of the limbs despite its structure and its involvement in joint pathology. Based on the laxity of the joint capsule it was concluded that invasive interventions at the respiratory tract with dislocation of the arytenoid cartilage can lead to incarceration of the synovial folds. After a trauma aero-synovitis or formation of hemarthrosis may occur, with subsequent fixation of the arytenoid in an abnormal position.
Subject(s)
Arytenoid Cartilage , Cricoid Cartilage , Joint Capsule , Adult , Aged , Aged, 80 and over , Arytenoid Cartilage/injuries , Arytenoid Cartilage/pathology , Arytenoid Cartilage/physiology , Biomechanical Phenomena , Cricoid Cartilage/injuries , Cricoid Cartilage/pathology , Cricoid Cartilage/physiology , Female , Hemarthrosis/etiology , Humans , Immunohistochemistry , Joint Capsule/pathology , Joint Capsule/physiology , Joint Dislocations/etiology , Male , Middle AgedABSTRACT
UNLABELLED: Impaired movement of the cricoarytenoid joint with hoarseness and immobility of the vocal ligament may occur as a consequence of endotracheal intubation. Little is known about the cricoarytenoid joint capsule and its role in intubation. We investigated the joint capsules of 48 cricoarytenoid joints by means of gross anatomy microscopy, histology, and scanning electron microscopy; 30 unfixed cadaver larynges were also subjected to attempts to simulate traumata such as those that may occur during intubation trials. The larynges were intubated with the arytenoid tip entering the lumen of the tracheal tube or extubated with the cuff of the tube only partially deflated. Subsequently, i.e., after dissecting the left and right cricoarytenoid joint from each larynx, the morphologic changes induced experimentally were analyzed by using histologic methods. The cricoarytenoid joint was found to be lined by a wide joint capsule. Unexpectedly large and intensively vascularized synovial folds projected into the joint cavity. After simulation of intubation and extubation, histologic analysis revealed injuries to the synovial folds and joint surface impressions, but no trauma or rupture of the outer joint capsule. We conclude that laxity of the joint capsule and the large synovial folds are predisposing factors for intubation trauma of the cricoarytenoid joint, potentially leading to hemarthros and finally to cricoarytenoid joint dysfunction. IMPLICATIONS: The present study illustrates by morphological investigations and intubation experiments that laxity of the joint capsule and large synovial folds are predisposing factors for intubation trauma of the cricoarytenoid joint, potentially leading to hemarthrosis and finally to cricoarytenoid joint dysfunction.
Subject(s)
Intubation, Intratracheal/adverse effects , Joint Capsule/injuries , Larynx/injuries , Adult , Aged , Aged, 80 and over , Chondrocytes/physiology , Chondrocytes/ultrastructure , Female , Humans , Joint Capsule/pathology , Larynx/pathology , Male , Microscopy, Electron, Scanning , Middle AgedABSTRACT
Fifty-five hospital-treated patients with the ICD-10 diagnosis of recurrent depressive episode(s) were classified according to the Newcastle Depressive Diagnostic Scale as having either psychogenic (n = 25) or endogenous (n = 30) depression and interviewed using the Composite International Diagnostic Interview and the Questionnaire for Assessment of Motivation to Seek Psychotherapy. The two groups were found to differ significantly from one another in two Motivation to Seek Psychotherapy subscales ("layman's etiology" and "general expectations from therapy"). The motivation to seek psychotherapy was greater in patients with psychogenic depression than in patients with endogenous depression. Nonetheless, psychotherapy is indispensable in treating endogenous depression, especially for patients under situational stress or at risk of suicide.