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Related papers: New Measurement Resolves Key Astrophysical Fe XVII…

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Band oscillator strengths for electronic transitions in CO were obtained at the Synchrotron Radiation Center of the University of Wisconsin-Madison. Our focus was on transitions that are observed in interstellar spectra with the Far…

Astrophysics · Physics 2009-11-06 S. R. Federman , M. Fritts , S. Cheng , K. M. Menningen , David C. Knauth , K. Fulk

There have been many reports of non-statistical effects in neutron-capture measurements. However, reports of deviations of reduced-neutron-width distributions from the expected Porter-Thomas (PT) shape largely have been ignored. Most of…

The stability of the linear chain structure of three $\alpha$ clusters for $^{12}$C against the bending and fission is investigated in the cranking covariant density functional theory, in which the equation of motion is solved on a 3D…

Nuclear Theory · Physics 2020-07-22 Z. X. Ren , S. Q. Zhang , P. W. Zhao , N. Itagaki , J. A. Maruhn , J. Meng

Context. The I(15.01 A)/I(16.78 A) emission line intensity ratio in Fe XVII has been reported to deviate from its theoretical value in solar and stellar X-ray spectra. This is attributed to opacity in the 15.01 A line, leading to a…

Astrophysics · Physics 2009-11-13 S. J. Rose , M. Matranga , M. Mathioudakis , F. P. Keenan , J. S. Wark

A new $^{11}$Be($d,p$)$^{12}$Be transfer reaction experiment was carried out in inverse kinematics at 26.9$A$ MeV, with special efforts devoted to the determination of the deuteron target thickness and of the required optical potentials…

Betatron oscillation is a commonly known phenomenon in laser or beam driven plasma wakefield accelerators. In the conventional model, the plasma wake provides a linear focusing force to a relativistic electron, and the electron oscillates…

Accelerator Physics · Physics 2023-03-06 Yulong Liu , Ming Zeng

A new measurement is presented of the $^6$Li(n,$\alpha$)t cross section from 245 keV to 10 MeV using a $^{252}$Cf fission chamber with $^6$LiI(Eu) and Cs$_2$LiYCl$_6$:Ce (CLYC) scintillators which act as both target and detector. Neutron…

Nuclear Experiment · Physics 2017-09-12 Leo E. Kirsch , M. Devlin , S. M. Mosby , J. A. Gomez

The Fermilab Booster - built more than 40 years ago - operates well above the design proton beam intensity of 4x10**12 ppp. Still, the Fermilab neutrino experiments call for even higher intensity of 5.5x10**12 ppp. A multitude of intensity…

Accelerator Physics · Physics 2013-02-01 Y. Alexahin , N. Eddy , E. Gianfelice-Wendt , V. Lebedev , W. Marsh , W. Pellico , K. Triplett

We constrain the linear and quadratic bias parameters from the configuration dependence of the three-point correlation function (3PCF) in both redshift and projected space, utilizing measurements of spectroscopic galaxies in the Sloan…

Within the domain of optical frequency comb systems operating in the mid-infrared, extensive exploration has been undertaken regarding critical parameters such as stabilization, coherence, or spectral tunability. Despite this, certain…

We study the nature of motion in a 3D potential composed of perturbed elliptic oscillators. Our technique is to use the results obtained from the 2D potential in order to find the initial conditions generating regular or chaotic orbits in…

Astrophysics of Galaxies · Physics 2012-06-26 Nicolaos D. Caranicolas , Euaggelos E. Zotos

Radiative emission lines from nitrogen and its ions are often observed in nebulae spectra, where the N$^{2+}$ abundance can be inferred from lines of the 2p4f configuration. In addition, intensity ratios between lines of the 2p3p -- 2p3s…

Atomic Physics · Physics 2015-03-17 Xiaozhi Shen , Jiguang Li , Per Jönsson , Jianguo Wang

High pressure X-ray diffraction measurements have been carried out on the intermetallic semiconductor FeGa$_3$ and the equation of state for FeGa$_3$ has been determined. First principles based DFT calculations within the GGA approximation…

Weak lensing surveys that can potentially place strong constraints on dark energy parameters can only do so if the source redshift means and error distributions are very well known. We investigate prospects for controlling errors in these…

Astrophysics · Physics 2009-11-13 Hu Zhan , Lloyd Knox

We use an electric-dipole laser-driven transition to precisely measure the cyclotron-frequency ratios of the pairs $^{42}$Ca$^+$-$^{40}$Ca$^+$, $^{44}$Ca$^+$-$^{40}$Ca$^+$ and $^{48}$Ca$^+$-$^{40}$Ca$^+$ in a 7-tesla Penning trap. A single…

We present a study of baryon ground states and low lying excitations of non-strange and strange baryons. The results are based on seven gauge field ensembles with two dynamical light Chirally Improved (CI) quarks corresponding to pion…

High Energy Physics - Lattice · Physics 2015-06-12 Georg P. Engel , C. B. Lang , Daniel Mohler , Andreas Schaefer

We calculate perturbatively the normalized spatial skewness, $S_3$, and full three-point correlation function (3PCF), $\zeta$, induced by gravitational instability of Gaussian primordial fluctuations for a biased tracer-mass distribution in…

Astrophysics · Physics 2009-10-31 Ari Buchalter , Marc Kamionkowski

A new instrument is required to accommodate the need for increased portability and accuracy in laser power measurement above 100 W. Reflection and absorption of laser light provide a measurable force from photon momentum exchange that is…

Instrumentation and Detectors · Physics 2021-02-10 Lorenz Keck , Gordon Shaw , René Theska , Stephan Schlamminger

The [$^{12}$C II] emission at 158 $\mu$m is a key cooling line of the interstellar medium and traces gas kinematics in spectrally resolved observations. Its spectral profile is often modified by optical depth effects. The intrinsic line…

We compute the real-space power spectrum and the redshift-space distortions of galaxies in the 2dF 100k galaxy redshift survey using pseudo-Karhunen-Loeve eigenmodes and the stochastic bias formalism. Our results agree well with those…

Astrophysics · Physics 2009-10-07 Max Tegmark , Andrew J. S. Hamilton , Yongzhong Xu