Tomosipo: Fast, flexible, and convenient 3D tomography for complex scanning geometries in Python

Abstract Generalised Parton Distributions (GPDs) offer a way of imaging nucleons through 3D tomography. They can be accessed experimentally in processes such as Deeply Virtual Compton Scattering (DVCS) and Deeply Virtual Meson Production (DVMP), where a high energy electron scatters from a quark inside a nucleon and a high energy photon or meson is produced as a result. Jefferson Lab has recently completed its energy upgrade and Hall B houses the new, large-acceptance CLAS12 detector array optimised for measurements of DVCS and DVMP in the newly accessible kinematic regime. Measurements on the proton and neutron are complementary and both are necessary to facilitate access to the full set of GPDs and enable their flavour separation. Neutron DVCS and DVMP are possible with the use of a deuteron target – the first CLAS12 experiment with which has started taking data this year. To enable exclusive reconstruction of DVCS and neutral-meson DVMP, a dedicated detector for recoiling neutrons – the Central Neutron Detector (CND) – was integrated into CLAS12. We present the first CLAS12 deuteron-target experiment, with a focus on the performance of the CND.

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Full wavefield 3D tomography: a case study in ITF research funding

First Break ◽

10.3997/1365-2397.26.1288.28411 ◽

2008 ◽

Vol 26 (6) ◽

Author(s):

M. Joswig

Keyword(s):

Research Funding ◽

3D Tomography

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Source parameter determination of local earthquakes in Korea using moment tensor inversion of single station data

Bulletin of the Seismological Society of America ◽

10.1785/bssa0890041077 ◽

1999 ◽

Vol 89 (4) ◽

pp. 1077-1082 ◽

Cited By ~ 1

Author(s):

So Gu Kim ◽

Nadeja Kraeva

Keyword(s):

Moment Tensor ◽

Source Parameters ◽

Moment Tensor Inversion ◽

P Wave ◽

Parameter Determination ◽

Reverse Fault ◽

3D Tomography ◽

Single Station ◽

Slip Event

Abstract The purpose of this investigation is to determine source parameters such as focal mechanism, seismic moment, moment magnitude, and source depth from recent small earthquakes in the Korcan Peninsula using broadband records of three-component single station. It is very important and worthwhile to use a three-component single station in Korea because for most Korean earthquakes it is not possible to read enough first motions of P-wave arrivals because of the poor coverage of the seismic network and the small size (ML 5.0 or less) of the events. Furthermore the recent installation of the very broadband seismic stations in Korea and use of a 3D tomography technique can enhance moment tensor inversion to determine the source parameters of small earthquakes (ML 5.0 or less) that occur at near-regional distances (Δ ≤ 500 km). The focal solution for the Youngwol earthquake of 13 December 1996 is found to be a right-lateral strike slip event with a NE strike, and the Kyongju earthquake of 25 June 1997 is found to be an oblique reverse fault with a slight component of left-lateral slip in the SE direction.

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