Analyzing #397

Variation of the parameters

Added by Vratislav Chudoba about 5 years ago. Updated over 4 years ago.

Status:

Открыта

Start date:

11/15/2019

Priority:

Нормальный

Due date:

Assignee:

Ivan Muzalevsky

% Done:

82%

Category:

Target version:

Description

Initial form of the ⁹Li missing mass will be determined in this issue together with input parameters. All variations of the stated parameters will be reported as an individual subtask of this issue.

The initial parameters:

number	parameter	value	unit
1	beam energy	beamDet thickness: 630 micron of Si
2*	thin SSD calibration parameters	pars for 2 thin detector (ssd_20u_2.cal) from issue 284 pars for 1 3 and 4 detectors from issue 391 (SSD_20u_1_cal.txt, SSD_20u_3_cal.txt SSD_20u_4_cal.txt )
3	thick SSD calibration parameters	issue 391
4	central DSD calibration parameters	issue 391
5	thin detector front dead layer	not used	mcm
6	thin detector rear dead layer	not used	mcm
7	thick SSD front dead layer	issue 391	mcm
8	thin detector position	issue 293	mm
9	thick detector position	issue 293	mm
10	central DSD position	(0,0,323)	mm
11	target density (same pressure as for ⁷H)	0.0020646	g.cm^-3
12	target density, low	0.001005	g.cm^-3
13**	full target thickness	6	mm
14	target mylar window thickness	3.5	mcm
15	target stainless steel window thickness	6	mcm
16***	CsI calibration parameters	not used
17	map of thickness for thin SSD	issue 392
18	target selection	circle of 9 mm radius with center in ( 0.4673,0.0262) mm at the target plane
19	MWPC positions	MWPC1 (-0.9,-3,-815) MWPC2 (0.3,-1.55,-270)	mm

* Energy deposit in the first layer of side telescopes is calculated according to the map of thickness. Calibration parameters are used exclusively for particle identification.
** Target is taken as a cylinder of homogeneous thickness for the purposes of reconstruction.
*** When needed, identification of ⁹Li is performed without calibration parameters using the CsI response in channel values.

Two expositions are at disposal:

for the thin gaseous target (be10_ct_39* and be10_ct_40*)
for the thick gaseous target (be10_ct_*)

Provide the resulting spectrum together with the mean value of the ground state in two separate comments:

one spectrum from all telescopes for the thin target;
one spectrum from all telescopes for the thick target and four spectra for individual telescopes.

Subtasks

History

#1 Updated by Ivan Muzalevsky about 5 years ago

Description updated (diff)

#2 Updated by Vratislav Chudoba about 5 years ago

Description updated (diff)

#3 Updated by Ivan Muzalevsky about 5 years ago

Description updated (diff)

#4 Updated by Ivan Muzalevsky about 5 years ago

Description updated (diff)

The content was deleted on 17.01.2020. The deleted results were incorrect.

#5 Updated by Ivan Muzalevsky about 5 years ago

Description updated (diff)

#6 Updated by Ivan Muzalevsky almost 5 years ago

Description updated (diff)

#7 Updated by Vratislav Chudoba almost 5 years ago

Description updated (diff)
Assignee set to Ivan Muzalevsky

#8 Updated by Ivan Muzalevsky almost 5 years ago

Description updated (diff)
Assignee deleted (~~Ivan Muzalevsky~~)

#9 Updated by Vratislav Chudoba almost 5 years ago

Description updated (diff)
Assignee set to Ivan Muzalevsky

#10 Updated by Ivan Muzalevsky almost 5 years ago

Description updated (diff)

#11 Updated by Ivan Muzalevsky over 4 years ago

Summed spectrum from all 4 telescopes for thin target¶

Green lines - coincidence with 9Li

The position of the g.s. is 0.048 MeV which was estimated as a mean value of the main peak of the black histogram

Separated spectra from 4 telescopes for thick target¶

Red lines - ground state selection

Ground state positions (means of red histograms):
-0.118 MeV (776 events)
0.359 MeV (634 events)
0.085 MeV (712 events)
0.149 MeV (711 events)

Summed spectrum from all 4 telescopes for thick target¶

Green lines - coincidence with 9Li

From the summed spectrum the g.s. position was calculated as a statistical average from 4 values:
position = (-0.118071*776 + 0.358727*634 + 0.0849232*712 + 0.149297*711)/2833 = 0.107 MeV