IPAC2011 - List of Authors (Ogando, F.)

Paper	Title	Page
TUPC126	Indirect Measurement of Power Deposition on the IFMIF/EVEDA Beam Dump by means of Radiation Chambers	1314
	D. Rapisarda, J.M. Arroyo, B. Brañas, A. Ibarra, D. Iglesias, C. Oliver CIEMAT, Madrid, Spain F. Ogando UNED, Madrid, Spain
	Funding: Work partially supported by Spanish Ministry of Science and Innovation under project AIC10-A-000441 and ENE2009-11230 The beam stop of the IFMIF/EVEDA accelerator will be a copper cone receiving a total power of ~1 MW, coming from 9 MeV D⁺ at 125 mA. The mechanical stresses in this beam dump come mainly from the thermal gradients generated in the cone, being therefore related with the power deposition profile. Anomalous situations such as beam misalignments or incorrect focusing can lead to variations in this profile outside the normal operation range. These variations must be detected and corrected for beam dump protection. Due to the interaction between D⁺ and the copper cone important neutron and gamma fluxes are generated around the beam dump (10¹⁰ – 10¹¹ n/cm²/s, 10¹⁰ p/cm²/s) with a spatial profile which is directly linked to the power deposition. In this work, a diagnostic based on a set of radiation chambers is proposed to measure on-line this radiation field, giving indirect information about the power deposition on the beam dump. The sensitivity of the radiation field to the power deposition profile is demonstrated and the diagnostic strategy explained, establishing the main specifications and requirements of the detectors.

TUPS045	IFMIF/EVEDA Beam Dump Shielding: Optimized Design of the Front Part	1635
	M. García, D. Lopez, A. Mayoral, F. Ogando, J. Sanz, P. Sauvan UNED, Madrid, Spain J.M. Arroyo, B. Brañas CIEMAT, Madrid, Spain
	The Beam Dump of the IFMIF/EVEDA accelerator prototype, designed to stop deuteron beam with energy up to 9 MeV and a maximum beam power of 1.12 MW, needs to fulfill radioprotection requirements. The deuteron beam collides with the beam stop and neutron and photon sources are produced. The objective of this paper is to design and justify the front part of the local shielding of the Beam Dump that complies with radiation limits for workers during beam-off phases. This shielding must allow unrestricted maintenance operations inside the vault, where the accelerator is located, after a reasonable cooling time after shutdown. In doing so, two main handicaps have been overcome. On one hand, the reliability of the traditionally used Monte Carlo codes such as MCNPX and PHITS has demonstrated to be very poor for deuteron transport at these low energies. In order to solve this lack, the MCUNED code using TENDL library is proposed to be used for deuteron transport and the prediction of the neutron and photon sources. On the other hand, the lack of space in the area dedicated to the last part of the accelerator demands a specially optimized shielding solution.

Paper

Title

Page

Indirect Measurement of Power Deposition on the IFMIF/EVEDA Beam Dump by means of Radiation Chambers

1314

D. Rapisarda, J.M. Arroyo, B. Brañas, A. Ibarra, D. Iglesias, C. Oliver
CIEMAT, Madrid, Spain
F. Ogando
UNED, Madrid, Spain

Funding: Work partially supported by Spanish Ministry of Science and Innovation under project AIC10-A-000441 and ENE2009-11230
The beam stop of the IFMIF/EVEDA accelerator will be a copper cone receiving a total power of ~1 MW, coming from 9 MeV D⁺ at 125 mA. The mechanical stresses in this beam dump come mainly from the thermal gradients generated in the cone, being therefore related with the power deposition profile. Anomalous situations such as beam misalignments or incorrect focusing can lead to variations in this profile outside the normal operation range. These variations must be detected and corrected for beam dump protection. Due to the interaction between D⁺ and the copper cone important neutron and gamma fluxes are generated around the beam dump (10¹⁰ – 10¹¹ n/cm²/s, 10¹⁰ p/cm²/s) with a spatial profile which is directly linked to the power deposition. In this work, a diagnostic based on a set of radiation chambers is proposed to measure on-line this radiation field, giving indirect information about the power deposition on the beam dump. The sensitivity of the radiation field to the power deposition profile is demonstrated and the diagnostic strategy explained, establishing the main specifications and requirements of the detectors.

TUPS045

IFMIF/EVEDA Beam Dump Shielding: Optimized Design of the Front Part

1635

M. García, D. Lopez, A. Mayoral, F. Ogando, J. Sanz, P. Sauvan
UNED, Madrid, Spain
J.M. Arroyo, B. Brañas
CIEMAT, Madrid, Spain

The Beam Dump of the IFMIF/EVEDA accelerator prototype, designed to stop deuteron beam with energy up to 9 MeV and a maximum beam power of 1.12 MW, needs to fulfill radioprotection requirements. The deuteron beam collides with the beam stop and neutron and photon sources are produced. The objective of this paper is to design and justify the front part of the local shielding of the Beam Dump that complies with radiation limits for workers during beam-off phases. This shielding must allow unrestricted maintenance operations inside the vault, where the accelerator is located, after a reasonable cooling time after shutdown. In doing so, two main handicaps have been overcome. On one hand, the reliability of the traditionally used Monte Carlo codes such as MCNPX and PHITS has demonstrated to be very poor for deuteron transport at these low energies. In order to solve this lack, the MCUNED code using TENDL library is proposed to be used for deuteron transport and the prediction of the neutron and photon sources. On the other hand, the lack of space in the area dedicated to the last part of the accelerator demands a specially optimized shielding solution.