SY-EPC-LPC R2E-EPC R2E Environment

Intro.

LHC Layout

Irrad. Damages

2011-2012 Irrad. Measured Levels

2015 (2016) Irrad. Measured Levels

2017-2023 Irrad. Expected Levels

HL-LHC Irrad.Expected Levels

R2E Mitigation Program

Irrad. Expected Spectra

Introduction

LHC environement is specific, being different from known radiation environements like space or nuclear plants, for 2 main reasons:

Type of radation and particle type and energy ranges.
Failure dependance, not as critical as in space applications (acceptable non-null failure rate).

LHC Layout

Irradiations conditions will be dependent on the machine location, regarding identified main sources (combinations possible in some locations):

Collimator-like Losses (beam cleanning, injection protection and dump protection).
Particles secondaries (debris from beam collisions at expermiments mainly lost in the accelerator part adjacent to the experiments).
Beam-Gas interaction. (collisions of beam particles with residual gas; gas-density is non-zero in vacuum)

LHC Sensitive to radiation Areas after R2E Mitigation Program (re-location + shielding) .png

Irradiation Expected Damages

Electronic devices exposed to radiation can experience 3 different types of radiation damage:

T.I.D. : Total Ionising Dose (cumulative).
N.I.E.L. : Non-Ionising Energy Loss (cumulative), 1 MeV equivalent neutron fluence. (Displacement Damage).
S.E.E. : Single Event Effect, proportionnal to High Energy Hardon fluence (with Energies above a few MeV typically 20 MeV), and also depending on the component sensitivity to the Thermal Neutrons (E < 0.5 eV).

A very basic file is provided below with number of equipements per location, giving an estimate of the number of events which can be expected based on the High Energy Hadrons Fluence and each converter sensitivity.

SY-EPC LHC Events Irradiation Calculator .xls, and for consultation only .htm

Many radmon (radiation monitors) are installed in the tunnel, and can be accessible through this website.
See below the radmons of particular interest for EPC Converters.

RR13: 1LM12S & 1LM11S
RR17: 1RM13S & 1RM12S
RR53: 5LM12S & 5LM11S
RR57: 5RM10S & 5RM09S
RR73: 7LM05S
RR77: 7RM07S

R2E Mitigation Program

An overview of different future and past actions on irradiated areas is provided below.

Area	R2E Mitigation Actions
Area	Shielding	Relocation	Other
Tunnel LHC60A-08V 752 units			FGC Lite (>LS2 (2018..2019))
RR13/17, RR53/57 LHC120A-10V 72 units LHC600A-10V 56 units LHC4-6-8kA-08V 60 units	Already done (LS1:2013) EDMS N°1182068	HL-LHC? (Additionnal constraint to HL-LHC Project Vertical SC-Links)	R2E-Power Converters? (>LS2 (2018..2019))
RR73/77 LHC120A-10V 20 units LHC600A-10V 48 units	Already done (2010)	HL-LHC? (Additionnal constraint to HL-LHC Project Horizontal SC-Links +UJ76 Civil Re-work)	R2E-Power Converters? (>LS2 (2018..2019)) + Collimator balance: Pt3 / Pt7
UA(s), UJ23, UJ87 Some local exception in Point 6 "sea level" expected (Th. n. excepted) LHC120A-10V 08 units UJ23 + 08 units UJ87	Already done (2010)

Area	R2E Mitigation Actions
Area	Shielding	Relocation	Other
Tunnel LHC60A-08V 752 units			FGC Lite (>LS2 (2018..2019))
UJ14/16 LHC120A-10V 10 units LHC600A-10V 16 units LHC4-6-8kA-08V 04 units	Already done (2011-12) EDMS N°1182068	Already done (LS1:2013) New Location: UL14/16
RR13/17, RR53/57 LHC120A-10V 72 units LHC600A-10V 56 units LHC4-6-8kA-08V 60 units	Already done (LS1:2013) EDMS N°1182068		R2E-Power Converters? (>LS2 (2018..2019))
UJ56 LHC120A-10V 05 units LHC600A-10V 7+1 units LHC4-6-8kA-08V 2 units (1 Inner Triplet system in total)		Already done (LS1:2013) New Location: UL55/56
RR73/77 LHC120A-10V 20 units LHC600A-10V 48 units	Already done (2010)		R2E-Power Converters? (>LS2 (2018..2019)) + Collimator balance: Pt3 / Pt7
UJ76 LHC600A-40V 12 units	Already done (2010)	Already done (LS1:2013) New Location: TZ76 EDMS N°977085	Collimator balance: Pt3 / Pt7
UA(s), UJ23, UJ87 Some local exception in Point 6 "sea level" expected (Th. n. excepted) LHC120A-10V 08 units UJ23 + 08 units UJ87	Already done (2010)

R2E Mitigation Program (re-location + shielding) planning - overview
- Current Current - History History

[2011; 2012] Irradiations Measured Levels

[2015] Irradiations Measured Levels

An important R2E mitigation program was decided (spread in the period 2010..2014) to minimize radiation in the LHC machine. See the goal-levels for the LHC machine once all mitigations actions are completed, levels then to be taken in account in the R2E Converter Redesign Program.
An overview of the radiation environment at the LHC in light of R2E irradiation test activities .pdf
Radiation to electronics - R2E, presented at Chamonix in 2016-01, by Salvatore Danzeca .pdf, .pptx
HL-LHC integration meeting n51: R2E in 2016-08, by Salvatore Danzeca .pdf, .pptx

Area	Levels Measured for 4 fb^-1for @ 6.5 TeV
Area	Dose [Gy/year]	1MeV neutrons eq. [nb/(cm².year)]	E>20MeV hadrons [/(cm².year)]	Th. neutron Ratio [n.th / ..]
Tunnel (ARC MB) LHC60A-08V 752 / 752 units	0.8(?) _?	?	1.5E8	3-8
UL14/16 LHC120A-10V 10 units LHC600A-10V 14+2x1 units LHC4-6-8kA-08V 2x2 units (2 Inner Triplet systems in total relocated at the safer place: 50% reduction expected on levels)	<0.5	(?)	2E6	10-20
RR13/17 LHC120A-10V 36 units LHC600A-10V 28 units LHC4-6-8kA-08V 30 units	? _1.6	? _3.2E9	1.4E7	1-5
RR53/57 LHC120A-10V 36 units LHC600A-10V 28 units LHC4-6-8kA-08V 30 units	? _1.6	? _3.2E9	9.17E6 _?	1-5
RR73/77 LHC120A-10V 20 units LHC600A-10V 48 units	? _1.6	? _3.2E9	1.57E7 _8E8(?)	1-5
UA/J(s), TZ76, UJ33, UL55/56, USC55 Some local exception in Point 6 "sea level" expected (Th. n. excepted)	< 0.02 _1.6	< 4E7 _4E7	< 1E7 _1E7	???

R2E Mitigation Levels (after re-location + shielding R2E program)

[2016] Irradiations Measured Levels

Area	Levels Measured for 40 fb^-1for @ 6.5 TeV
Area	Dose [Gy/year]	1MeV neutrons eq. [nb/(cm².year)]	E>20MeV hadrons [/(cm².year)]	Th. neutron Ratio [n.th / ..]
Tunnel (ARC MB Cell 12-16) LHC60A-08V 192 / 752 units	(?)	(?)	5E8	3-8
Tunnel (ARC MB Cell 18-34) LHC60A-08V 588 / 752 units	(?)	(?)	1.55E8	3-8
UL14/16 LHC120A-10V 10 units LHC600A-10V 14+2x1 units LHC4-6-8kA-08V 2x2 units (2 Inner Triplet systems in total relocated at the safer place: 50% reduction expected on levels)	<0.5	1E8(?)	6E6	10-20
RR13/17 LHC120A-10V 36 units LHC600A-10V 28 units LHC6kA-08V 30 units LHC4kA-08V 04 units	? _1.6	? _3.2E9	5E7	1-5
RR53/57 LHC120A-10V 36 units LHC600A-10V 28 units LHC6kA-08V 30 units LHC4kA-08V 04 units	? _1.6	? _3.2E9	1.5E8 _?	1-5
RR73/77 LHC120A-10V 20 units LHC600A-10V 48 units	? _1.6	? _3.2E9	1.4E7 _8E8(?)	1-5
UA/J(s), TZ76, UJ33, UL55/56, USC55 Some local exception in Point 6 "sea level" expected (Th. n. excepted)	< 0.02 _1.6	< 4E7 _4E7	< 1E7 _1E7	???

Radiation levels and converters location after LS1

[2017; 2018] Irradiations Expected Levels

This period ends up with LS2, where new radiation-tolerant converters will be installed. In 2017-02, FGClite controllers were installed on all LHC60A-08V.
Status and evolution of radiation on 60A power converters, by Ruben Garcia - presented in TE-TM .indico
Update on the expected radiation levels for HL-LHC, by Ruben Garcia - presented in HL-LHC 8th collaboration week in 2018-10-17. .pdf

Area	Levels expected for [35; 45] fb^-1
Area	Dose [Gy/year]	1MeV neutrons eq. [nb/(cm².year)]	E>20MeV hadrons [/(cm².year)]	Th. neutron Ratio [n.th / ..]
Tunnel (ARC MB Cell 12-16) LHC60A-08V 192 / 750 units	(?)	(?)	5E8	3-8
Tunnel (ARC MB Cell 18-34) LHC60A-08V 556 / 750 units	(?)	(?)	1.55E8	3-8
UL14/16 LHC120A-10V 10 units LHC600A-10V 14+2x1 units LHC8kA-08V 2 units LHC6kA-08V 2 units (2 Inner Triplet systems in total)	<0.5 (?)	(?)	6E6	10-20
RR13/17 LHC120A-10V 36 units LHC600A-10V 28 units R2E-LHC6kA-08V 26 units R2E-LHC4kA-08V 04 units	0.4 (?)	(?)	[2; 4]E8	1-5
RR53/57 LHC120A-10V 36 units LHC600A-10V 28 units LHC6kA-08V 26 units LHC4kA-08V 04 units	0.4 (?)	(?)	[3; 4]E8	1-5
RR73/77 LHC120A-10V 20 units LHC600A-10V 48 units	0.4 (?)	(?)	[1; 3]E7 RR73₂₀₁₈:7E7	1-5
UA/J(s), TZ76, UJ33, UL55/56, USC55 Some local exception in Point 6 "sea level" expected (Th. n. excepted)	< 0.02	< 4E7	< 1E7	???

Comments
Converters	Exposed 1006 Tunnel..... 750 RR13/17.... 94 RR53/57.... 94 RR73/77.... 68	LHC60A-08V....... 750 LHC120A-10V..... 092 LHC600A-10V..... 104 LHC4kA-08V....... 008 LHC6kA-08V....... 052		FGClite controllers are installed in tunnel only.
Converters	Exposed 30 UL14/16.... 30	LHC120A-10V...... 10 LHC600A-10V...... 16 LHC6kA-08V........ 02 LHC8kA-08V........ 02		Level is sufficiently low not to upgrade these converters, nor their controllers.

Radiation levels and converters location after LS1

[2020; 2025] Irradiations Expected Levels

R2E-LHC600A, R2E-HL-LHC600A, R2E-LHC4-6-8kA converters are installed, with FGClite being installed in remaining places (RR1/5/7).

Area	Levels expected for [35; 45] fb^-1
Area	Dose [Gy/year]	1MeV neutrons eq. [nb/(cm².year)]	E>20MeV hadrons [/(cm².year)]	Th. neutron Ratio [n.th / ..]
Tunnel (ARC MB Cell 12-16) LHC60A-08V 192 / 750 units	(?)	(?)	5E8	3-8
Tunnel (ARC MB Cell 18-34) LHC60A-08V 556 / 750 units	(?)	(?)	1.55E8	3-8
UL14/16 LHC120A-10V 10 units LHC600A-10V 14+2x1 units LHC8kA-08V 2 units LHC6kA-08V 2 units (2 Inner Triplet systems in total) LHC600A-40V 2 units	<0.5 (?)	(?)	6E6	10-20
RR13/17 LHC120A-10V 36 units R2E-LHC600A-10V 28 units R2E-LHC6kA-08V 26 units R2E-LHC6kA-08V * 04 units * installed with 5kA DCCT	0.4 (?)	(?)	5E8 _TCL-close 5E7 _TCL-open	1-5
RR53/57 LHC120A-10V 36 units R2E-LHC600A-10V 28 units R2E-LHC6kA-08V 26 units R2E-LHC6kA-08V * 04 units * installed with 5kA DCCT	0.4 (?)	(?)	2.5E8 _TCL-close 2.5E7 _TCL-open	1-5
RR73/77 LHC120A-10V 20 units R2E-LHC600A-10V 48 units R2E-HL-LHC600A-10V 02 units	0.4 (?)	(?)	1.4E7	1-5
UA/J(s), TZ76, UJ33, UL55/56, USC55 Some local exception in Point 6 "sea level" expected (Th. n. excepted)	< 0.02	< 4E7	< 1E7	???

Comments
Converters	Exposed 1008 Tunnel..... 750 RR13/17.... 94 RR53/57.... 94 RR73/77.... 70	LHC60A-08V................... 750 LHC120A-10V.................. 92 R2E-HL-LHC600A-10V.. 002 R2E-LHC600A-10V........ 104 R2E-LHC6kA-08V.......... 060		R2E-LHC600A-10V & R2E-LHC6kA-08V are installed in LS2. FGClite controllers are installed in tunnel and RR1/5/7. R2E-HL-LHC600A-10V (2) are installed in RR7.
Converters	Exposed 32 UL14/16... 32	LHC120A-10V...... 10 LHC600A-10V...... 16 LHC600A-40V...... 02 LHC6kA-08V........ 02 LHC8kA-08V........ 02		LHC600A-40V is now exposed to radiation in UL14/16 (low level still).

Radiation levels and converters location between LS2 & LS3

[2025; 2035] Irradiations Expected Levels

HL-LHC upgrade will impact a lot the radiation levels on all sensitive places, since the luminosity will increase from 30 fb^-1 to 250 fb^-1 per year, for a total of 4 000 fb^-1 for HL-LHC era (12 years).

A common factor can very often being used:
1 Gy <=> 1E9 E>20MeV hadrons [/(cm².year)] <=> 1E10 1MeV neutrons eq. [nb/(cm².year)] <=> 1E10 thermal neutrons [nb/(cm².year)]

Area	Max Levels @ Nominal Machine Parameters Data provided below already include safety margin
Area	Dose [Gy/year]	1MeV neutrons eq. [nb/(cm².year)]	E>20MeV hadrons [/(cm².year)]	Comments
Tunnel R2E-HL-LHC60A-10V 72 units (072 ( cell[12;16] Pt1,2,5)	08x 12L(1/5): <3 08x 12R(1/5): <3 08x 12L/R2: 1.4 48x 14/16-L/R-1/2/5: 1.4	08x 12L(1/5): 3E10 08x 12R(1/5): 3E10 08x 12L/R2: 1.6E10 48x 14/16-L/R-1/2/5: 1.6E10	08x 12L(1/5): 3E9 08x 12R(1/5): 3E9 08x 12L/R2: 2.4E9 48x 14/16-L/R-1/2/5: 2.4E9	72 units considered most exposed to radiations.. Radiation main origin: experience collision debris. Pt2: Highly dependant from TCLD Target (Collimator Long Dispersion suppressor) operational settings. Scaling factor: integrating luminosity. Pt1,5_Atlas,CMS. Highly dependant from machine operation mode / optics. 72=3_(1,2,5)x3_(12,14,16)x4_cvsx2_sym
Tunnel LHC60A-08V 606 units R2E-HL-LHC60A-10V 072 units (550x cell[18;34] Pt12345678) (120x cell[12;16] Pt3,4,6,7,8)	1.4	1.6E10	2.4E9	72 units used as.. Radiation main origin: interaction of the beam with residual gas. Scaling factor: integrating intensity, pressure. 72 units, rotation installed qty vs pt1,5,8 units. pt8_LHCb. Highly dependant from machine operation mode / optics.
RR13/17 R2E-HL-LHC120A-10V 36 units R2E-LHC600A-10V 28 units R2E-LHC6kA-08V 26 units R2E-LHC6kA-08V 04 units * installed with 5kA DCCT	level-0: 15 level-1: 25	level-0: 7E10 level-1: 7E10	level-0: 1.0E10 level-1: 1.4E10	Radiation main origin: Atlas collision debris. Scaling factor: luminosity + TCL6 collimator. Level-1 (10) considered as level-0 (3) up to 2019-04.
RR53/57 R2E-HL-LHC120A-10V 36 units R2E-LHC600A-10V 28 units R2E-LHC6kA-08V 26 units R2E-LHC6kA-08V 04 units * installed with 5kA DCCT	level-0: 15 level-1: 25	level-0: 7E10 level-1: 7E10	level-0: 1.0E10 level-1: 1.4E10	Radiation main origin: CMS collision debris. Scaling factor: luminosity + TCL6 collimator. Level-1 (10) considered as level-0 (3) up to 2019-04.
RR73/77 R2E-LHC600A-10V 48 units R2E-HL-LHC120A-10V 20 units R2E-HL-LHC600A-10V 02 units	0.5	4E9	2E8	Radiation main origin: lost protons in momentum & betatron collimators. Scaling factor: colimation losses.
UL14/16 R2E-HL-LHC120A-10V 16 units R2E-LHC600A-10V 02 units	0.01 close to US15/17 0.10 in UL14/16_middle 1.00 close to UJ14/16	2E8 close to US15/17 1E9 in UL14/16_middle 1E10 close to UJ14/16	2E7 close to US15/17 1E8 in UL14/16_middle 1E9 close to UJ14/16	High gradient vs location. The R2E-LHC600A is used at 200A. Thermal neutron levels in UJ can be high x10 or x100! E>20 MeV.
UA/J(s), TZ76, UJ33, UR15/57 Some local exception in Point 6 "sea level" expected (Th. n. excepted)	0.01	[5E6; 2.5E7]	[1; 5]E6	streaming through holes (UA in pt6 to be considered for equipment in line-of-sight or close-by

Comments
Converters	Exposed 1028 Tunnel..... 750 RR13/17.... 104 RR53/57.... 104 RR73/77.... 70 UL14/16.... 18	LHC60A-08V................... (678 - n) R2E-HL-LHC60A-10V.... n (72.min) R2E-HL-LHC120A-10V.. 116+016_UL14/16 R2E-HL-LHC600A-10V.. 002 R2E-LHC600A-10V........ 104+002_UL14/16 R2E-LHC6kA-08V.......... 060		R2E-LHC600A&kA Power Converters are already in place, since installed in LS2. HL-LHC120A (92) and R2E-HL-LHC60A (n - 72.min) required converters are installed in LS3 (radiation stress + availability). Addit. R2E-HL-LHC120A (24) are installed for Q4-Q5-Q6 correctors in RR1/5, with RD2 kA converters removed from RR1/5 (4x in total). Some converter stays in UL14/16 (LHC600A-40V?)
Infrastructure	HL-LHC	Creation of UR galleries in point 1/5 IT, allowing installing new converters for HL-LHC Inner Triplet.

HL-LHC radiation level specification document v.1.1 2024-08
HL-LHC radiation level specification document v.1.0 2020-09
HL-LHC radiation level specification document and review @ 2019-12
Last Official R2E-validated Radiation levels @ 2019-09
Update on 60A radiation levels in LHC arc (2019-09 .pdf)
HL-LHC radiation levels in the IP1-IP5 LSS tunnel and RRs, from data here (2019-04 .pdf)
HL-LHC Integration Meeting: ... R2E mapping in DS areas of IR1 and IR5... (2018-11 .pdf)
HL-LHC TCC (2017-11 .pdf)
Informal meeting Yves + Ruben (2018-01-31) in Yves's Office + MCWG (2018-01 .pdf)
6th Annual HiLumi Collaboration Meeting, Paris, November 14-16 2016, from data here (2016-11 .pdf)
R2E Mitigation Levels (after HL-LHC Upgrade foreseen in 2023), from data here (2013-11 .pdf)

Irradiation Expected Spectra

See following curves detailling the radiation type vs LHC locations (UJ/RR locations dominated by neutrons since shielded, then stopping the protons more efficiently than neutrons) .

Particle energy spectra (lethargy) and Inverse cumulative high energy hadron fluence for UJ-14/16 & RR-13/17 in the LHC < 2011-12
(more shielded planned to be added in end of 2011).
Curves normalized to a nominal year of operation.

Particle energy spectra (lethargy) and Inverse cumulative probability plots representative for tunnel areas in the LHC.
Spectra normalized one proton-proton collision (referred to as a primary in the label). Peak seen at lower Ej for the proton fluence due to (n,p) reactions with Nitrogen in air.
Curves normalized to the high Ej hadron fluence.

References

An overview of the radiation environment at the LHC in light of R2E activities .pdf