Star-fst-l mailing list

[Carl Gagliardi <c-gagliardi AT tamu.edu>]

Hi Flemming—

 

I hadn’t imagined the HLT filter as the final answer.  Rather, I had imagined that it would select the small fraction of cosmic events that project to the vicinity of the FST for a small data stream.  Then that stream can be run through Fast Offline to provide the TPC tracks, followed by detailed FST-specific studies – multiplicities, timing, amplitudes, hit correlations, etc.

 

Am I completely out to lunch?

Carl

 

 

From: videbaek <videbaek AT bnl.gov>
Sent: Tuesday, November 23, 2021 6:34 AM
To: Hongwei Ke <kehw AT rcf.rhic.bnl.gov>
Cc: Xu Sun <sunxuhit AT gmail.com>; Star-fst L <star-fst-l AT lists.bnl.gov>; Carl Gagliardi <c-gagliardi AT tamu.edu>; Aschenauer Elke-Caroline <elke AT bnl.gov>
Subject: Re: [Star-fst-l] FST Position

 

Hi Hongwei, Thanks for implementing this. I think we could consider strengthening th criteria. This woud allow any track that hits th cycinder to be tagged. One suggestion would be to require one of two conditions a) cylinder hit AND hit in ZjQcmQRYFpfptBannerStart

This Message Is >From an External Sender

This message came from outside your organization.

ZjQcmQRYFpfptBannerEnd

Hi Hongwei,

Thanks for implementing this.

I think we could consider strengthening th criteria. This woud allow any 

track that hits th cycinder to be tagged. One suggestion would be to 

require

one of two conditions a) cylinder hit AND hit in second disk (182) or b) 

hit in disk 1 (148) and hit in disk(2). This would match the criteria 

for the two trigger evpw/e and ewpdw.tof , and give higher probability 

for also hits in stgc.

Of course the reduction is still large w/o this extra criteria.

F

On 2021-11-22 23:15, Hongwei Ke wrote:

> Hi Fleming and all

> 

> Thank you for the info. Here is what I have implemented and ready for

> test.

> 

>           * I use bField = 1e-6 Tesla instead of zero to make sure all

> extrapolation functions work properly. This value is chosen

> arbitrarily. As long as it is not zero, the math should be correct.

>           * To "match FST", I extrapolate TPC tracks to three surfaces.

> 

>           * A cylinder: r = 36cm, 148 <= z <= 182cm  # cylinder geometry is

> easier to deal with

>           * A disk r <= 36, z = 148

>           * A disk r <= 36, z = 182

>           * These values can be changed easily. If needed, they can be

> implemented as Run Control parameters that can be turned by shift crew

> run-by-run.

> 

>           * The track extrapolation is done in sequence. If there is one track

> hits any of those three surfaces, it is a match and the event will be

> tagged.

>           * From my standalone test on a signal daq file from run 22326045,

> 748 out of 30374 events are tagged. The ratio is ~2.5%.

> 

> Best regards,

> Hongwei Ke

> 

>> On Nov 22, 2021, at 4:05 PM, videbaek <videbaek AT bnl.gov> wrote:

>> 

>> Hi Hongwei,

>> cc Xu

>> 

>> With the actual positions  the z range should rather be 148 to 182,

>> As Xu says you can ether use a square for the xy cut or maybe better

>> a circle with radius say 36(40)

>> 

>> F.

>> 

>> On 2021-11-22 15:59, Xu Sun wrote:

>> Hi Hongwei,

>> The radius of the FST disk is about 31cm, therefore, I quote 40cm

>> for

>> both x and y.

>> Not sure why Carl quotes y = 0, maybe Carl could comment.

>> Best,

>> Xu

>> On Mon, Nov 22, 2021 at 3:57 PM Hongwei Ke <kehw AT rcf.rhic.bnl.gov>

>> wrote:

>> Hi Xu,

>> Carl’s number in his Nov 20 email to star-ops are a little

>> different.

>> Would it be possible for L4 to identify those events with a cosmic

>> track that projects through the rectangle:

>> -40 < x < +40

>> 140 < z < 180

>> At y=0

>> Which one should I use?

>> Best regards,

>> Hongwei Ke

>> On Nov 22, 2021, at 12:28 PM, Xu Sun <sunxuhit AT gmail.com> wrote:

>> Hi Hongwei,

>> As discussed in today's 10 clock meeting, please find the FST

>> position below:

>> x & y: -40 to 40 cm

>> z: 140 to 180 cm.

>> Hope this helps.

>> Best,

>> Xu

>  _______________________________________________

> Star-fst-l mailing list

> Star-fst-l AT lists.bnl.gov

> https://urldefense.com/v3/__https://lists.bnl.gov/mailman/listinfo/star-fst-l__;!!KwNVnqRv!Tij1GWmARo0T_DKXPzcM1_Rw5YuPH00_5WA-UwwMR3Edp5294fCnpmXUm-UHYyLhAjE$ 

> 

> --

> Flemming Videbaek

> senior scientist

> videbaek @ bnl.gov [1]

> Brookhaven National Lab

> Physics Department

> Bldg 510D

> Upton, NY 11973

> 

> phone: 631-344-4106

> cell     :  631-681-1596

> 

> 

> 

> Links:

> ------

> [1] https://urldefense.com/v3/__http://bnl.gov__;!!KwNVnqRv!Tij1GWmARo0T_DKXPzcM1_Rw5YuPH00_5WA-UwwMR3Edp5294fCnpmXUm-UHwoJbTxE$ 

-- 

Flemming Videbaek

senior scientist

videbaek @ bnl.gov

Brookhaven National Lab

Physics Department

Bldg 510D

Upton, NY 11973

phone: 631-344-4106

cell     :  631-681-1596