Understanding of the C–H stretch region of infra-red spectroscopy: an analysis of the final state wavefunctions

2021 ◽  
Vol 23 (15) ◽  
pp. 9176-9188
Author(s):  
Swati Yadav ◽  
Subrata Banik ◽  
M. Durga Prasad
Keyword(s):  
Final States ◽  
Final State ◽  
Infra Red ◽  
State Wavefunctions

The nature of wavefunctions associated with the final states in the CH stretch region of several medium sized molecules are analysed.

scholarly journals RECENT τ LEPTON RESULTS FROM BABAR

2014 ◽  
Vol 35 ◽  
pp. 1460440
Author(s):  
ALBERTO LUSIANI
Keyword(s):  
Standard Model ◽  
Branching Fractions ◽  
Charged Particles ◽  
Babar Collaboration ◽  
Final States ◽  
Final State ◽  
Experimental Knowledge ◽  
Electron Positron ◽  
The Standard Model ◽  
Positron Collisions

We report recent measurements on τ leptons obtained by the BABAR collaboration using the entire recorded sample of electron-positron collisions at and around the Υ(4S) (about 470fb-1). The events were recorded at the PEP-II asymmetric collider at the SLAC National Accelerator Laboratory. The measurements include high multiplicity τ decay branching fractions with 3 or 5 charged particles in the final state, a search for the second class current the τ decay τ → πη′ν, τ branching fractions into final states containing two KS mesons, [Formula: see text], with h = π, K, and preliminary measurements of hadronic spectra of τ decays with three hadrons (τ- → h-h+h-ντ decays, where h = π, K). The results improve the experimental knowledge of the τ lepton properties and can be used to improve the precision tests of the Standard Model.

SEARCH FOR NEW PHYSICS IN eμX DATA AT THE TEVATRON USING SLEUTH: A QUASI-MODEL-INDEPENDENT SEARCH STRATEGY FOR NEW PHYSICS

2001 ◽  
Vol 16 (supp01b) ◽  
pp. 888-890
Author(s):  
◽  
BRUCE KNUTESON
Keyword(s):  
Standard Model ◽  
Search Strategy ◽  
New Physics ◽  
Beyond The Standard Model ◽  
Final States ◽  
Final State ◽  
The Standard Model ◽  
Model Independent

We present a quasi-model-independent search for physics beyond the standard model. We define final states to be studied, and construct a rule that identifies a set of variables appropriate for any particular final state. A new algorithm ("Sleuth") searches for regions of excess in the space of those variables and quantifies the significance of any detected excess. After demonstrating the sensititvity of the method, we apply it to the semi-inclusive channel eμX collected in ≈108 pb -1 of [Formula: see text] collisions at [Formula: see text] at the DØ experiment at the Fermilab Tevatron. We find no evidence of new high pT physics in this sample.

scholarly journals Electron Momentum Spectroscopy

1986 ◽  
Vol 39 (5) ◽  
pp. 587 ◽  
Author(s):  
IE McCarthy
Keyword(s):  
Impulse Approximation ◽  
High Electron ◽  
Final States ◽  
Final State ◽  
Structure Information ◽  
Plane Wave Impulse Approximation ◽  
Ion Structure ◽  
Spectroscopic Factors ◽  
Electron Momentum Spectroscopy ◽  
Energy And Momentum

For sufficiently high electron energies (greater than a few hundred eV) and sufficiently low recoil momenta Oess than a few atomic units) the differential cross section for the non-coplanar symmetric (e,2e) reaction on an atom or molecule depends on the target and ion structure only through the target-ion overlap. Experimental criteria for the energy and momentum are that the apparent structure information does not change when the energy and momentum are varied. The plane-wave impulse approximation is a sufficient description of the reaction mechanism for determining spherically averaged squares of momentum-space orbitals for atoms and molecules and for coefficients describing initial- and final-state correlations. For mainly uncorrelated initial states, spectroscopic factors for final states belonging to the same manifold are uniquely determined. For molecules, summed spectroscopic factors can be compared for different ion manifolds. For atoms, summed spectroscopic factors and higher-momentum profiles require the dist~rted-wave impulse approximation.

The Early and Final States of an Epidemic in a Large Heterogeneous Population by a Small Initial Number of Infectives

1994 ◽  
Vol 26 (03) ◽  
pp. 671-689
Author(s):  
Steven M. Butler
Keyword(s):  
Random Number ◽  
Death Process ◽  
Time Interval ◽  
Final States ◽  
Birth And Death Process ◽  
Initial Number ◽  
Threshold Behavior ◽  
Final State ◽  
Epidemic Process ◽  
Susceptibility To Infection

This paper describes the early and final properties of a general S–I–R epidemic process in which the infectives behave independently, each infective has a random number of contacts with the others in the population, and individuals vary in their susceptibility to infection. For the case of a large initial number of susceptibles and a small (finite) initial number of infectives, we derive the threshold behavior and the limiting distribution for the final state of the epidemic. Also, we show strong convergence of the epidemic process over any finite time interval to a birth and death process, extending the results of Ball (1983). These complement some results due to Butler (1994), who considers the case of a large initial number of infectives.

Implementation of the CMS-SUS-19-006 analysis in the MadAnalysis 5 framework (supersymmetry with large hadronic activity and missing transverse energy; 137 fb−1)

2020 ◽  
pp. 2141007
Author(s):  
Malte Mrowietz ◽  
Sam Bein ◽  
Jory Sonneveld
Keyword(s):  
Transverse Momentum ◽  
Transverse Energy ◽  
Final States ◽  
Missing Transverse Energy ◽  
Final State ◽  
Data Set ◽  
Proton Proton ◽  
Missing Transverse Momentum ◽  
Proton Data ◽  
Two Jets

We present the MadAnalysis 5 implementation and validation of the analysis Search for supersymmetry in proton-proton collisions at 13 TeV in final states with jets and missing transverse momentum (CMS-SUS-19-006). The search targets signatures with at least two jets and large missing transverse momentum in the all-hadronic final state. The analyzed luminosity is 137 fb[Formula: see text], corresponding to the Run 2 proton-proton data set recorded by the CMS detector at 13 TeV. This implementation has been validated in a variety of simplified models, by comparing derived cut flow tables and histograms with information provided by the CMS collaboration, using event samples that we simulated for the purpose of this re-implementation study. The validation is found to reproduce the signal acceptance in most cases.

scholarly journals Observation of Ionization of Laser Excited Atoms by Synchrotron Radiation

1984 ◽  
Vol 86 ◽  
pp. 128-131
Author(s):  
J.M. Bizau ◽  
F. Wuilleumier ◽  
P. Gerard ◽  
P. Dhez ◽  
B. Carré ◽  
...  
Keyword(s):  
Synchrotron Radiation ◽  
Photoelectron Spectroscopy ◽  
Oscillator Strengths ◽  
Final States ◽  
Initial State ◽  
Final State ◽  
Core Electron ◽  
Output Mirror ◽  
Initial States ◽  
A New Technique

We have begun a program to measure oscillator strengths of autoionizing resonances that result from a transition in the VUV between a laser excited initial state and a final state in which a core electron is promoted. These measurements demonstrate a new technique to combine synchrotron radiation, laser pumping, and photoelectron spectroscopy.Measurements of the energy positions of autoionizing resonances have been honed to a fine art over the past 50 years. Total cross section measurements and the parameters that describe autoionizing resonances have been determined. Most of these studies have been made from the dipole allowed ground state. Recently autoionizing resonances have been observed from excited initial states and from ion initial states. We have heard several talks, at this meeting which described some of this type of research. In the measurements to be described in this paper, laser radiation is combined with synchrotron radiation, as shown schematicaly in Figure 1, to study the photoionization from excited initial states to continuum final states or to autoionizing final states. Continuum radiation from the Aneau de Collisions d’Orsay (ACO), which is installed at the Universite de Paris-Sud, in Orsay France, is monochromatized by a toroidal grating monochromator (TGM) and is focused by a toroidal output mirror on to a weakly collimated sodium beam emanating from a furnace mounted on the axis of a cylinderical mirror analyzer (CMA). This electron spectrometer is used to study the kinetic energy distribution of the ejected photoelectrons produced by the interaction of the photon beam with the focused synchrotron radiation.

scholarly journals Patterns and paschen-back analogue in the stark-effect for neon

1929 ◽  
Vol 123 (791) ◽  
pp. 80-103 ◽  
Keyword(s):  
Quantum Number ◽  
Stark Effect ◽  
Selection Rule ◽  
Theoretical Calculations ◽  
Zeeman Effect ◽  
Final States ◽  
Outer Electron ◽  
Initial State ◽  
Final State ◽  
Left Handed

While the Stark-effect has not been studied so extensively as the Zeeman-effect, either in the experiments or in their interpretations, many of the more prominent features have been observed and have received adequate explanation on the quantum theory. Among these may be mentioned the patterns characteristic of the different series in the singlet system of parhelium. The variety of observed patterns in the Stark-effect, as contrasted with the normal Zeeman-effect found for all series of this system, arises from a differential action of the external electric field on the initial and final states, and a breaking down of the usual selection rule for the azimuthal quantum number. Some simplification is brought about, however, by the fact that only the absolute value of the quantum number m has any meaning in the interpretation of these photographs, since the action of the field is the same for right or left-handed motion of the outer electron in its orbit. This results in asymmetrical patterns for all the lines. The number of components observed in the patterns of individual lines of parhelium is in accord with the theoretical view that the vector j (here equal to l ) is resolved along the direction of the applied field to give the integral m values ranging from - j to + j , and that the usual selection rule holds for m . The displacements and intensities are in excellent agreement with the theoretical calculations based on the perturbation theory of quantum mechanics. The spacing of the sub-levels identified by ± m in the initial state is decidedly irregular in the Stark-effect as compared with the normal Zeeman-effect, where the displacements are proportional to m . The Zeeman order of the levels is usually reversed, in fact, and the spacing is uneven. Displacements in the final state are theoretically very small, and have not been observed with certainty. In the Stark-effect for orthohelium (triplet system) the same group of patterns was observed. An explanation of these observations, which is slightly less satisfactory than that obtained with parhelium, has been made by similar methods, neglecting the electron spin. Thus the m values were again given ranges determined in each case by the l of the outer electron, and not by the j for the whole atom. Most of the plates failed to reveal any of the fine structure of the normal orthohelium spectrum.

scholarly journals Structure in the secondary hydrogen spectrum—Part V

1926 ◽  
Vol 113 (764) ◽  
pp. 368-419 ◽  
Keyword(s):  
Quantum Number ◽  
Vibrational State ◽  
Final States ◽  
Vibrational Quantum Number ◽  
Vibrational States ◽  
Rydberg Constant ◽  
Infra Red ◽  
Preliminary Account ◽  
Before And After ◽  
State Of Affairs

In a previous paper entitled “Structure in the Secondary Hydrogen Spectrum,” Part IV, it was shown that there were a number of bands associated with Fulcher’s bands. It now appears that these and other related bands form a set of band systems whose null lines are connected by a Rydberg-Ritz formula. This formula has the normal value of the Rydberg constant, as is the case with the formula found by Fowler to connect the heads of some of the helium bands. This discovery makes it possible to apportion the effects observed as between electron jumps and vibration jumps, a matter which had to be left open in the previous paper (p. 740). The present paper deals only with the Q branches which are the most strongly developed and have been investigated most fully. A preliminary account of some of the results has been published a letter to ‘Nature,’ but the numbering of the vibrational states of the H α bands proposed therein has since been abandoned. It will be shown that all the lines of Fulcher’s red bands arise as a result of transitions in which the total quantum number (electron jump) changes from 3 to 2 and the vibrational quantum number is unchanged. In the part of the band denoted by A in “Structure,” Part IV, the vibrational state has the lowest possible quantum number both before and after the transition. I shall indicate this state of affairs by the symbol 0 → 0. The corresponding vibrational states in the parts denoted by B, C, D, E and F are, both initially and finally, 1, 2, 3, 4 and 5, and I shall denote these transitions by 1 →1, 2 → 2 , 3 → 3 , 4 → 4 and 5 → 5 respectively. The different lines in part A all have the same electron jump (3 → 2) and the same vibration state (0 → 0) but have different rotational jumps either of the molecule as a whole or of the emitting electron or of both. This statement will be equally true if the letter A is replaced by any of the letters B, C, D, E or F, except that the vibrational jump 0 0 is replaced by 1 → 1, 2 → 2, etc. In the present paper I shall confine my attention to the Q branches so that all the rotational transitions here dealt with are of the type m + ½ → m + ½ , m = 1, 2, 3, 4, 5, etc. (see Part IV, p. 749). Fulcher’s green bands also have the same electron jumps (3 → 2), but in these bands the vibrational quantum number is higher by unity in the initial than in the final states. Thus for the various green bands denoted by the letters A, B, C, D, E and F the vibrational transitions are 1 → 0, 2 → 1, 3 → 2, 4 → 3, 5 → 4 and 6 → 5 respectively. In addition to these, bands with the same electron jump (3 → 2) can be found in the infra-red with the vibrational jumps 0 → 1, 1 → 2, 2 → 3, 3 → 4 and 4 → 5 and others on the side of the green towards the violet which correspond to the vibration jumps 2 → 0, 3 → 1, 4 → 2, 5 → 3 and 6 → 4, and a few lines which may correspond to the vibration jumps 3 → 0 and 5 → 2. All these lines have the electron jump 3 → 2 and are the band analogue of the single line H α in the line spectrum of the hydrogen atom. For this reason it is convenient to refer to this system of bands as the H α bands.

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