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in creator/contributor: "Tanner, D. B."

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A Search for Scalar Chameleons with ADMX

Scalar fields with a"chameleon" property, in which the effective particle mass is a function of its local environment, are common to many theories beyond the standard model and could be responsible for dark energy. If these fields couple weakly to the photon, they could be detectable through the afterglow effect of photon-chameleon-photon transitions. The ADMX experiment was used in the first chameleon search with a microwave cavity to set a new limit on scalar chameleon-photon coupli… more

Date: April 26, 2010

Creator: Rybka, G.; Hotz, M.; Rosenberg, L. J.; Asztalos, S. J.; Carosi, G.; Hagmann, C. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

A SQUID-based microwave cavity search for dark-matter axions

Axions in the {mu}eV mass range are a plausible cold dark matter candidate and may be detected by their conversion into microwave photons in a resonant cavity immersed in a static magnetic field. The first result from such an axion search using a superconducting first-stage amplifier (SQUID) is reported. The SQUID amplifier, replacing a conventional GaAs field-effect transistor amplifier, successfully reached axion-photon coupling sensitivity in the band set by present axion models and sets the… more

Date: October 21, 2009

Creator: Asztalos, S. J.; Carosi, G.; Hagmann, C.; Kinion, D.; van Bibber, K.; Hotz, M. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Status of the U.S. Dark Matter Axion Search

We describe the status of a sensitive search for halo axions with masses in the {mu}eV range. A tunable large-volume and low-loss microwave cavity is operated at low temperature in a strong magnetic field. Resonant Primakoff conversion of axions into photons takes place when the cavity frequency is matched to the axion mass. No positive signal has been found so far, and we are able to exclude hadronic axions as the dominant halo component over a significant axion mass range. Future plans for a … more

Date: October 4, 2000

Creator: Hagmann, C.; Asztalos, S.; Daw, E.; Golubev, N. A.; Kinion, D.; Moltz, D. M. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

A Proposed Search for Dark-Matter Axions in the 0. 6--16. Mu. Ev Range

A proposed experiment is described to search for dark-matter axions in the mass range 0.6--16 {mu}eV. The method is based on the Primakoff conversion of axions into monochromatic microwave photons inside a tunable microwave cavity in a large volume high field magnet. This proposal capitalized on the availability of two Axicell magnets from the MFTF-B fusion machine at LLNL. Assuming a local dark-matter density in axions of {rho}{sub a}= 0.3 GeV/cm{sup 3}, the axion would be found or ruled out a… more

Date: November 1, 1991

Creator: Hagmann, C.; Moltz, D. M.; Turner, M. S.; Sikivie, P.; Sullivan, N. S.; Tanner, D. B. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

A proposed search for dark-matter axions in the 0.6--16 {mu}eV range

Date: November 1, 1991

Creator: Hagmann, C.; Moltz, D. M.; Turner, M. S.; Sikivie, P.; Sullivan, N. S.; Tanner, D. B. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Laser-synchrotron hybrid experiments: ``A photon to tickle, a photon to poke``

In this paper we present the preliminary results from a new experimental technique to synchronize the pulses from a mode-locked NdYAG laser to the light pulses in the VUV storage ring at the National Synchrotron Light Source (NSLS). We describe a method to electronically change the delay time between the laser pulses and the synchrotron pulses. We also illustrate a method to overlap the synchrotron pulses with the laser pulses in space and time. Preliminary results will be presented for two exp… more

Date: December 31, 1991

Creator: Ederer, D. L.; Rubensson, J. E.; Mueller, D. R.; Shuker, R.; O`Brien, W. L.; Jai, J. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

INVESTIGATION OF COHERENT EMISSION FROM THE NSLS VUV RING.

Bursts of coherent radiation are observed from the NSLS VUV ring near a wavelength of 7 mm. The bursts occur when the electron beam current (I) exceeds a threshold value (I{sub th}), which itself varies with ring operating conditions. Beyond threshold, the average intensity of the emission is found to increase as (I-I{sub th}){sup 2}. With other parameters held nearly constant, the threshold current value is found to increase quadratically with synchrotron frequency, indicating a linear depende… more

Date: March 1, 1999

Creator: Carr, G. L.; Kramer, S. L.; Murphy, J. B.; Laveigne, J.; Lobo, R. P. S.; Reitze, D. H. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Results of a Search for Cold Flows of Dark Matter Axions

No Description Available.

Date: May 17, 2005

Creator: Duffy, L.; Sikivie, P.; Tanner, D. B.; Asztalos, S.; Hagmann, C.; Kinion, D. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Time resolved spectroscopy using synchrotron infrared pulses

Electron synchrotron storage rings, such as the VUV ring at the National Synchrotron Light Source (NSLS), produce short pulses of infrared (IR) radiation suitable for investigating the time-dependent phenomena in a variety of interesting experimental systems. In contrast to other pulses sources of IR, the synchrotron produces a continuum spectral output over the entire IR (and beyond), though at power levels typically below those obtained from laser systems. The infrared synchrotron radiation (… more

Date: September 1, 1997

Creator: Carr, G. L.; Lobo, R. P. S. M.; Hirschmugl, C. J.; LaVeigne, J.; Reitze, D. H. & Tanner, D. B.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Time-resolved far-infrared experiments at the National Synchrotron Light Source. Final report

A facility for time-resolved infrared and far-infrared spectroscopy has been built and commissioned at the National Synchrotron Light Source. This facility permits the study of time dependent phenomena over a frequency range from 2-8000cm{sup {minus}1} (0.25 meV-1 eV). Temporal resolution is approximately 200 psec and time dependent phenomena in the time range out to 100 nsec can be investigated.

Date: October 12, 1999

Creator: Tanner, D. B.; Reitze, D. H. & Carr, G. L.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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A proposed search for dark-matter axions in the 0. 6--16. mu. eV range

A proposed experiment is described to search for dark-matter axions in the mass range 0.6--16 {mu}eV. The method is based on the Primakoff conversion of axions into monochromatic microwave photons inside a tunable microwave cavity in a large volume high field magnet, as described by Sikivie. This proposal capitalizes on the availability of two Axicell magnets from the decommissioned MFTF-B fusion machine at LLNL. Assuming a local dark-matter density in axions of {rho} = 0.3 GeV/cm{sup 3}, the a… more

Date: March 1, 1991

Creator: van Bibber, Karl; Sikivie, P.; Sullivan, N. S.; Tanner, D. B.; Turner, M. S. & Moltz, D. M.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Large-scale search for dark-matter axions

Early results from a large-scale search for dark matter axions are presented. In this experiment, axions constituting our dark-matter halo may be resonantly converted to monochromatic microwave photons in a high-Q microwave cavity permeated by a strong magnetic field. Sensitivity at the level of one important axion model (KSVZ) has been demonstrated.

Date: January 1, 1998

Creator: Hagmann, C. A.; Kinion, D.; Stoeffl, W.; Van Bibber, K.; Daw, E. J.; McBride, J. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

TIME-RESOLVED INFRARED SPECTROSCOPY IN THE U121R BEAMLINE AT THE NSLS

A facility for performing time-resolved infrared spectroscopy has been developed at the NSLS, primarily at beamline U12IR. The pulsed IR light from the synchrotron is used to perform pump-probe spectroscopy. The authors present here a description of the facility and results for the relaxation of photoexcitations in both a semiconductor and superconductor.

Date: July 19, 1999

Creator: Carr, G. L.; Laveigne, J. D.; Lobo, R. P. S. M.; Reitze, D. H. & Tanner, D. B.

Item Type: Article

Partner: UNT Libraries Government Documents Department