Internal cw parametric upconversion

Falk, Joel; See, Y.C.

doi:10.1063/1.89951

Cited by 14 publications

(14 citation statements)

References 12 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…For example the process x → ν e e + e − γ operates at a rate α/2π relative to the decay x → ν e e + e − and would have generated a γ ray burst which was not observed by the SMM satellite [25]. When combined with other arguments relating to energy deposition inside the supernova [26], as well as experimental bounds on fast ν τ decays [8,9], this rules out all lifetimes shorter than ∼ 10 8 s [27], forbidding the entire solution range for doublet neutrinos.…”

mentioning

confidence: 99%

Remarks on the KARMEN anomaly

1995

View full text Add to dashboard Cite

A recently reported anomaly in the time structure of signals in the KARMEN neutrino detector suggests the decay of a new particle x, produced in π + → µ + x with mass m x = 33.9 MeV. We discuss the constraints and difficulties in interpreting x as a neutrino. We show that a mainly-sterile neutrino scenario is compatible with all laboratory constraints, within narrow limits on the mixing parameters, although there are problems with astrophysical and cosmological constraints. This scenario predicts that appreciable numbers of other x-decay events with different origins and time structures should also be observable in the KARMEN detector.Such x-decay events should also be found in the LSND experiment and may be relevant to the search forν µ →ν e oscillations.(Published in Phys. Lett. B352 (1995) 365; erratum added June 1995)The KARMEN collaboration, which studies the interactions of neutrinos from the stopped π + decay chain at RAL, has recently reported an anomaly [1] in the timedependence of their signals. This anomaly suggests the production of a new weaklyinteracting neutral particle (call it x) in the initial π + decays, which travels with well determined velocity β x = v x /c ≃ 1/60 and decays in the detector after a mean flight path of 17.5 m. The distinctive feature of the x-events is their timing, apparently at a well determined interval 3.6µs after the arrival and prompt decay of the pion pulse (which determines β x ); however, the visible energy in the detector scintillator shows no anomaly, so x decays apparently deposit visible energy similar to typical neutrino interactions.The present note briefly discusses the interpretation of x as a massive neutrino. We show that a mainly-sterile neutrino scenario is compatible with all laboratory constraints, for either Dirac or Majorana options, within rather narrow bounds on the mixing parameters. There are some problems with astrophysical and cosmological constraints, but it is interesting nevertheless to explore the further implications for laboratory experiments which can test this interpretation directly. This scenario predicts that appreciable numbers of other x-decay events with different origins and time structures should also be observable in the KARMEN detector. Such x-decay events should also be found in the LSND experiment at LAMPF [2] and may be relevant to the ongoing search forν µ →ν e oscillations [3].If we postulate no other new particles below the pion mass, then the precise time structure [1] requires x production to go via one of the two-body modes π + → µ + x or π + → e + x . However the latter implies mass m x = 137.2 MeV (determined from β x ) and hence anomalously large visible x-decay energy, with mean value < T vis > ≃ 51MeV for x → µeν → eeννν or < T vis > ≃ 88 MeV for x → eeν, compared to neutrino interactions that typically give T vis ∼ 11−35 MeV [1]. We must therefore presume that x is produced via π + → µ + x, with m x = 33.9 MeV determined from β x . Assuming no new weak interactions, the standard decay mode is x → e − e ...

show abstract

mentioning

confidence: 99%

Remarks on the KARMEN anomaly

1995

View full text Add to dashboard Cite

show abstract

“…2 Note that large values of µ ∼ O (1 TeV) can be obtained naturally in mSUGRA from the requirement of radiative electroweak symmetry breaking [6], while very large values of tan β ∼ O(50) are favored if one requires Yukawa coupling unification at the GUT scale; see Ref.…”

Section: Higgs Production In Association With Stausmentioning

confidence: 99%

Probing the SUSY Higgs boson couplings to scalar leptons at high-energy e+e− colliders

Datta¹,

Djouadi²,

Kneur³

2001

Physics Letters B

View full text Add to dashboard Cite

We discuss the production at e + e − colliders of Higgs bosons in association with both the scalar leptons and the lightest neutralinos in the Minimal Supersymmetric extension of the Standard Model. While the rates for associated Higgs production with neutralinos and first/second generation sleptons are rather tiny, the cross section for the production of the lightest Higgs boson h with scalar τ lepton pairs can reach the femtobarn level at c.m. energies at and above 500 GeV in favorable regions of the parameter space, making this process potentially detectable at a high-luminosity e + e − collider, in particular in the γγ option. This would provide a determination of the hττ coupling and opens up the possibility of measuring the parameter tan β.

show abstract

“…One method to enhance the efficiency has been intra-cavity upconversion. This was first demonstrated using lasers [4], but the efficiency was here limited by the intra-cavity loss originating from absorption in the nonlinear crystal. The (non-imaging) upconversion efficiency was reported to be 0.38% at best.…”

Section: Introductionmentioning

confidence: 99%

“…Upconversion has been investigated for decades but with a particularly strong focus in the late 1960s to mid 1980s [1][2][3][4][5][6][7]. However, one important parameter limiting the applications of the upconversion process has been the upconversion efficiency.…”

Section: Introductionmentioning

confidence: 99%

“…During the last thirty years only a tiny fraction of reported upconversion work has involved imaging. Using a diode-pumped, high finesse, solid-state laser at 1342 nm and a tapered diode laser at 765 nm, more than 300 mW of upconverted 488 nm light was generated in a periodicallypoled KTiOPO 4 (PPKTP) crystal. The power conversion efficiency from 765 nm to 488 nm was 32% [8].…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Enhanced 2D-image upconversion using solid-state lasers

Pedersen¹,

Karamehmedović²,

Dam³

et al. 2009

Opt. Express

View full text Add to dashboard Cite

Based on enhanced upconversion, we demonstrate a highly efficient method for converting a full image from one part of the electromagnetic spectrum into a new desired wavelength region. By illuminating a metal transmission mask with a 765 nm Gaussian beam to create an image and subsequently focusing the image inside a nonlinear PPKTP crystal located in the high intra-cavity field of a 1342 nm solid-state Nd:YVO 4 laser, an upconverted image at 488 nm is generated. We have experimentally achieved an upconversion efficiency of 40% under CW conditions. The proposed technique can be further adapted for high efficiency mid-infrared image upconversion where direct and fast detection is difficult or impossible to perform with existing detector technologies.

show abstract

Internal cw parametric upconversion

Abstract: The first demonstration of cw parametric upconversion inside a laser’s optical cavity is reported. Infrared radiation λ=3.39 μm was upconverted using a 5145-Å argon laser pump and a lithium niobate crystal.

Cited by 14 publications

References 12 publications

Remarks on the KARMEN anomaly

Remarks on the KARMEN anomaly

Probing the SUSY Higgs boson couplings to scalar leptons at high-energy e+e− colliders

Enhanced 2D-image upconversion using solid-state lasers

Contact Info

Product

Resources

About