Spruch, Larry
Overview
Works:  28 works in 42 publications in 2 languages and 555 library holdings 

Genres:  Technical reports Academic theses 
Roles:  Author 
Publication Timeline
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Most widely held works by
Larry Spruch
The ubiquitous atom by
Grace Marmor Spruch(
Book
)
2 editions published in 1974 in English and held by 478 WorldCat member libraries worldwide
"Based upon material from booklets in the series Understanding the atom, produced under the aegis of the United States Atomic Energy Commission."
2 editions published in 1974 in English and held by 478 WorldCat member libraries worldwide
"Based upon material from booklets in the series Understanding the atom, produced under the aegis of the United States Atomic Energy Commission."
21 astounding science quizzes by
Grace Marmor Spruch(
Book
)
2 editions published in 1982 in English and held by 37 WorldCat member libraries worldwide
2 editions published in 1982 in English and held by 37 WorldCat member libraries worldwide
Atomo omnipresente by
Grace Marmor Spruch(
Book
)
3 editions published between 1974 and 1977 in Spanish and held by 3 WorldCat member libraries worldwide
3 editions published between 1974 and 1977 in Spanish and held by 3 WorldCat member libraries worldwide
Upper bounds on electronatomic hydrogen scattering lengths by
Tony Randall(
Book
)
2 editions published in 1960 in English and held by 3 WorldCat member libraries worldwide
2 editions published in 1960 in English and held by 3 WorldCat member libraries worldwide
Low energy scattering by a compound system : positrons on hydrogen by
Larry Spruch(
Book
)
3 editions published between 1959 and 2015 in English and held by 3 WorldCat member libraries worldwide
3 editions published between 1959 and 2015 in English and held by 3 WorldCat member libraries worldwide
Theoretical Investigation of Atomic Structure and Scattering Processes(
Book
)
3 editions published between 1980 and 1987 in English and held by 3 WorldCat member libraries worldwide
Recent research results: Relativistic scattering in an external quasistatic electric field; Gauge invariant approximations for scattering in a strong external field; Extremum principle for relativistic bound state energies; Modified perturbation theory for scattering in a laser field. Lasers; Atomic scattering; Long range interactions
3 editions published between 1980 and 1987 in English and held by 3 WorldCat member libraries worldwide
Recent research results: Relativistic scattering in an external quasistatic electric field; Gauge invariant approximations for scattering in a strong external field; Extremum principle for relativistic bound state energies; Modified perturbation theory for scattering in a laser field. Lasers; Atomic scattering; Long range interactions
Bounds on scattering phase shifts for compound systems by
Tony Randall(
Book
)
3 editions published in 1960 in English and held by 3 WorldCat member libraries worldwide
An extension of recently developed methods determines a rigorous upper bound on 1/( k cot eta), where eta is the phase shift, for the general one channel scattering process. The method requires truncation of the various potentials, but it should generally be possible, in practice, to so truncate the potentials that the difference between the phase shifts of the original problem and of the problem for which a bound is obtained is insignificant. It is necessary to introduce, for compound system scattering, an absolute definition of the phase shift, not simply a definition modulo pi. The definition chosen is to take the projection of the full scattering wave function on the ground state wave function of the scattering system, and to treat the resultant one coordinate wave function as if it were the scattering wave function for a particle on a center of force. Though irrelevant with regard to the determination of a bound on cot eta, it is interesting that at least for some simple cases this definition automatically increases the phase shift by at least pi whenever the Pauli principle introduces a spatial node into the scattering wave func ion. The triplet scattering of electrons by H atoms provides an example. (Author)
3 editions published in 1960 in English and held by 3 WorldCat member libraries worldwide
An extension of recently developed methods determines a rigorous upper bound on 1/( k cot eta), where eta is the phase shift, for the general one channel scattering process. The method requires truncation of the various potentials, but it should generally be possible, in practice, to so truncate the potentials that the difference between the phase shifts of the original problem and of the problem for which a bound is obtained is insignificant. It is necessary to introduce, for compound system scattering, an absolute definition of the phase shift, not simply a definition modulo pi. The definition chosen is to take the projection of the full scattering wave function on the ground state wave function of the scattering system, and to treat the resultant one coordinate wave function as if it were the scattering wave function for a particle on a center of force. Though irrelevant with regard to the determination of a bound on cot eta, it is interesting that at least for some simple cases this definition automatically increases the phase shift by at least pi whenever the Pauli principle introduces a spatial node into the scattering wave func ion. The triplet scattering of electrons by H atoms provides an example. (Author)
Bounds on scattering phase shifts by
Larry Spruch(
Book
)
2 editions published in 1957 in English and held by 2 WorldCat member libraries worldwide
2 editions published in 1957 in English and held by 2 WorldCat member libraries worldwide
Bounds on elements of the s matrix for elastic scattering: one dimensional scattering by
Ralph Bartram(
Book
)
2 editions published in 1961 in English and held by 2 WorldCat member libraries worldwide
Multichannel scattering in which the scattering matrix cannot be diagonalized a priori is considered. The Schroedinger equation is cast intoA FORM IN WHICH THE POTENTIAL IS A REAL SYMMETRIC N by N matrix and the wave function is an N by 1 matrix. The equation for neutron protron scattering with tensor forces is written in matrix form with N equals to 2; the same is true for the problem of onedimensional scattering. Upper and lower bounds are determined on the elements of the S matrix, the N by N matrix which relates the N outgoing waves to the N incoming waves. (Author)
2 editions published in 1961 in English and held by 2 WorldCat member libraries worldwide
Multichannel scattering in which the scattering matrix cannot be diagonalized a priori is considered. The Schroedinger equation is cast intoA FORM IN WHICH THE POTENTIAL IS A REAL SYMMETRIC N by N matrix and the wave function is an N by 1 matrix. The equation for neutron protron scattering with tensor forces is written in matrix form with N equals to 2; the same is true for the problem of onedimensional scattering. Upper and lower bounds are determined on the elements of the S matrix, the N by N matrix which relates the N outgoing waves to the N incoming waves. (Author)
Atomic effects of beta decay in astrophysics and in elementary particle physics by Zonghua Chen(
)
1 edition published in 1988 in English and held by 2 WorldCat member libraries worldwide
The thesis consists mainly of two parts. The first part is a study of the boundstate $\beta$ decay of $\sp{187}$Re and its application in Astrophysics. There existed an uncertainty in the ratio $\rho\sb{b}$ of boundstate to continuum $\beta$ decay of $\sp{187}$Re in both theory and experiment. A more definite theoretical result of $\rho\sb{b}$ $\approx$ 1% is obtained by using singleconfiguration and multiconfiguration HartreeFockDirac approximations. The results obtained are close to those obtained by Williams, Fowler, and Koonin by a modified ThomasFermi model. The boundstate $\beta$ decay of $\sp{187}$Re at high temperatures is also studied. The second part of the thesis is a generalization of the ThomasFermi results of various energy contributions to the groundstate energy of a neutral atom. An analytical expression for the ratio of the electronelectron to electronnuclear interaction is obtained by the corrected ThomasFermi result, the ratio obtained gives a better agreement with the HartreeFock numerical results
1 edition published in 1988 in English and held by 2 WorldCat member libraries worldwide
The thesis consists mainly of two parts. The first part is a study of the boundstate $\beta$ decay of $\sp{187}$Re and its application in Astrophysics. There existed an uncertainty in the ratio $\rho\sb{b}$ of boundstate to continuum $\beta$ decay of $\sp{187}$Re in both theory and experiment. A more definite theoretical result of $\rho\sb{b}$ $\approx$ 1% is obtained by using singleconfiguration and multiconfiguration HartreeFockDirac approximations. The results obtained are close to those obtained by Williams, Fowler, and Koonin by a modified ThomasFermi model. The boundstate $\beta$ decay of $\sp{187}$Re at high temperatures is also studied. The second part of the thesis is a generalization of the ThomasFermi results of various energy contributions to the groundstate energy of a neutral atom. An analytical expression for the ratio of the electronelectron to electronnuclear interaction is obtained by the corrected ThomasFermi result, the ratio obtained gives a better agreement with the HartreeFock numerical results
On the eigenvalues which give upper and lower bounds on scattering phases by
Larry Spruch(
Book
)
2 editions published in 1956 in English and held by 2 WorldCat member libraries worldwide
2 editions published in 1956 in English and held by 2 WorldCat member libraries worldwide
ON THE EIGENVALUES WHICH GIVE UPPER AND LOWER BOUNDS ON SCATTERING PHASES (CLASSIC REPRINT) by
Larry Spruch(
Book
)
1 edition published in 2016 in English and held by 1 WorldCat member library worldwide
1 edition published in 2016 in English and held by 1 WorldCat member library worldwide
Bounds on the elements of the equivalent network for scattering in waveguides by
Larry Spruch(
Book
)
1 edition published in 1959 in English and held by 1 WorldCat member library worldwide
1 edition published in 1959 in English and held by 1 WorldCat member library worldwide
Bounds on scattering phase shifts: static central potentials by
Tony Randall(
)
1 edition published in 1960 in English and held by 1 WorldCat member library worldwide
1 edition published in 1960 in English and held by 1 WorldCat member library worldwide
Modification of effective range theory in the presence of a longrange r to the 4th potential(
Book
)
1 edition published in 1961 in English and held by 1 WorldCat member library worldwide
1 edition published in 1961 in English and held by 1 WorldCat member library worldwide
Heavy Particle Collisions(
Book
)
1 edition published in 1982 in English and held by 1 WorldCat member library worldwide
This report discusses nuclear resonances and the probability of Kshell ionization, effect of collisions on the emission of radiation, and asymmetric charge transfer
1 edition published in 1982 in English and held by 1 WorldCat member library worldwide
This report discusses nuclear resonances and the probability of Kshell ionization, effect of collisions on the emission of radiation, and asymmetric charge transfer
Modification of effective range theory in the presence of a longrange (1/r^4) potential by T. F O'Malley(
)
1 edition published in 1961 in English and held by 1 WorldCat member library worldwide
1 edition published in 1961 in English and held by 1 WorldCat member library worldwide
BOUNDS ON SCATTERING PHASE SHIFTS (CLASSIC REPRINT) by
Larry Spruch(
Book
)
1 edition published in 2016 in English and held by 1 WorldCat member library worldwide
1 edition published in 2016 in English and held by 1 WorldCat member library worldwide
Improved minimum principle for singlechannel scattering(
Book
)
1 edition published in 1962 in English and held by 1 WorldCat member library worldwide
The minimum principle for singlechannel scatter ing obtained previously required the introduction of channel radii for an incident relative kinetic energy E greater than zero. The channel radii, which greatly complicate the numerical calcula tions, no longer appear in recent formal theories of reations and they need not appear in the mini mum principle formulation. By projecting out all of the openchannel components from the full wave function, it is possible to eliminate the continuum states of the total Hamiltonian H originally present below E. The closedchannel Hamiltonian has only a discete spectrum below the inelastic threshold. By appropriately substract ing the contributions from the discrete portion of the spectrum, the closedchannel Hamiltonian can be used to obtain a minimum principle for k cot eta where eta is the phase shift. This min imum principle provides a rigorous criterion for determining the parameters in a trial function and for choosing among the numerical results ob tained with different trial functions. The meth od requires that one solve exactly the static approximation equation. (Author)
1 edition published in 1962 in English and held by 1 WorldCat member library worldwide
The minimum principle for singlechannel scatter ing obtained previously required the introduction of channel radii for an incident relative kinetic energy E greater than zero. The channel radii, which greatly complicate the numerical calcula tions, no longer appear in recent formal theories of reations and they need not appear in the mini mum principle formulation. By projecting out all of the openchannel components from the full wave function, it is possible to eliminate the continuum states of the total Hamiltonian H originally present below E. The closedchannel Hamiltonian has only a discete spectrum below the inelastic threshold. By appropriately substract ing the contributions from the discrete portion of the spectrum, the closedchannel Hamiltonian can be used to obtain a minimum principle for k cot eta where eta is the phase shift. This min imum principle provides a rigorous criterion for determining the parameters in a trial function and for choosing among the numerical results ob tained with different trial functions. The meth od requires that one solve exactly the static approximation equation. (Author)
Extrapolation of crosssection data to zero energy for longrange effective potentials(
Book
)
1 edition published in 1964 in English and held by 1 WorldCat member library worldwide
The effective onebody potential representing a particlecompoundsystem interaction usually has a very complicated shortrange behavior, but a relatively simple, and more or less known, longrange tail U which can be nonlocal and energydependent. With U present, the usual effectiverangetheory (ERT) expansion for a singlechannel scattering phase shift eta is inapplicable. Recent extensions of ERT include the effects of longrange potentials, but since eta then becomes very energydependent, one would need many terms to obtain the desired accuracy, so the results are of restricted use. We show that one can first solve, numerically, a onebody problem which includes only U, and then use a modified ERT expansion for the difference delta between eta and the phase shift due to U alone. Since the rapid energy dependence due to U is thus extracted out (exactly), terms in the expansion which depend upon the shortrange potential in the presence of U are more slowly varying in energy; they involve a number of adjustable parameters to be determined experimentally, but only a few are usually needed. The procedure thus makes possible the extrapolation of lowenergy scattering data down to zero energy, even when effective longrange potentials are present. (Author)
1 edition published in 1964 in English and held by 1 WorldCat member library worldwide
The effective onebody potential representing a particlecompoundsystem interaction usually has a very complicated shortrange behavior, but a relatively simple, and more or less known, longrange tail U which can be nonlocal and energydependent. With U present, the usual effectiverangetheory (ERT) expansion for a singlechannel scattering phase shift eta is inapplicable. Recent extensions of ERT include the effects of longrange potentials, but since eta then becomes very energydependent, one would need many terms to obtain the desired accuracy, so the results are of restricted use. We show that one can first solve, numerically, a onebody problem which includes only U, and then use a modified ERT expansion for the difference delta between eta and the phase shift due to U alone. Since the rapid energy dependence due to U is thus extracted out (exactly), terms in the expansion which depend upon the shortrange potential in the presence of U are more slowly varying in energy; they involve a number of adjustable parameters to be determined experimentally, but only a few are usually needed. The procedure thus makes possible the extrapolation of lowenergy scattering data down to zero energy, even when effective longrange potentials are present. (Author)
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Related Identities
 Spruch, Grace Marmor Author
 Rosenberg, Leonard Author
 O'Malley, Thomas Francis 1928
 Bartram, Ralph Author
 NEW YORK UNIV NY COURANT INST OF MATHEMATICAL SCIENCES
 Chen, Zonghua Author
 NEW YORK UNIV N Y COURANT INST OF MATHEMATICAL SCIENCES
 NEW YORK UNIV NY Dept. of PHYSICS
 New York University Institute of Mathematical Sciences Division of Electromagnetic Research
 WASHINGTON SQUARE COLL OF ARTS AND SCIENCE NEW YORK
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