[G8b_run] g8 meeting
Eugene Pasyuk
pasyuk at jlab.org
Mon Mar 25 12:36:39 EDT 2013
I booked B101 for locals.
-Eugene
----- Original Message -----
> From: "Patrick Collins" <pcollins at jlab.org>
> To: "Eugene Pasyuk" <pasyuk at jlab.org>
> Sent: Monday, March 25, 2013 12:33:06 PM
> Subject: Fwd: [G8b_run] g8 meeting
> Eugene,
> Where should the onsite people get together?
> Cheers,
> Patrick
> -------- Original Message --------
> Subject: [G8b_run] g8 meeting
> Date: Mon, 25 Mar 2013 15:50:55 +0000
> From: Ken Livingston <Kenneth.Livingston at glasgow.ac.uk>
> Reply-To: Kenneth.Livingston at glasgow.ac.uk
> Organization: University of Glasgow
> To: g8b <g8b_run at jlab.org>
> Hi All,
> I though it was already a done deal.
> Let's make it 11.00 Jlab time. Will you kick it off Eugene.
> Please add to the agenda at
> https://clasweb.jlab.org/rungroups/g8/wiki/index.php/Mar_26,_2013
> Instructions for offsite participants:
> https://clasweb.jlab.org/rungroups/g8/wiki/index.php/Instructions_for_off-site_participants
> Regards,
> Ken
> -------- Original Message --------
> Subject: Re: [G8b_run] Fwd: g8b TOF paddle issue
> Date: Mon, 25 Mar 2013 15:27:54 +0000
> From: Eugene Pasyuk <pasyuk at jlab.org> To: Kenneth Livingston
> <Kenneth.Livingston at glasgow.ac.uk> Hi Ken,
> It looks like the best time is tomorrow, Tuesday March 26 between
> 11:00 and 12:30 of JLab time http://doodle.com/ycqshd8fpnda66mx You
> pick the time.
> -Eugene
> ----- Original Message -----
> > From: "Eugene Pasyuk" <pasyuk at jlab.org> > To: "Kenneth Livingston"
> > <Kenneth.Livingston at glasgow.ac.uk> > Cc: "g8b run"
> > <g8b_run at jlab.org> > Sent: Wednesday, March 20, 2013 12:22:57 PM
> > Subject: Re: [G8b_run] Fwd: g8b TOF paddle issue
> >
> > Call-in instructions:
> >
> > ------------------------------------------------------------------------
> > Dial Toll-Free Number: 866-740-1260 (U.S. & Canada)
> > International Toll-Free Numbers: http://www.readytalk.com/intl >
> > Enter 7-digit access code, 7440953 followed by #
> >
> > -Eugene
> >
> > ----- Original Message -----
> > > From: "Ken Livingston" <Kenneth.Livingston at glasgow.ac.uk> > > To:
> > > "g8b run" <g8b_run at jlab.org> > > Sent: Wednesday, March 20, 2013
> > > 12:18:13 PM
> > > Subject: Re: [G8b_run] Fwd: g8b TOF paddle issue
> > >
> > > Hi All,
> > > I've made a very brief meeting page at
> > > https://clasweb.jlab.org/rungroups/g8/wiki/index.php/Mar_26,_2013
> > > > >
> > > Can you please upload any relevant files (eg Brian's plots).
> > >
> > > Cheers,
> > > Ken
> > >
> > >
> > > On 20/03/13 16:01, Eugene Pasyuk wrote:
> > > > So far 7 people responded to doodle poll. The earliest best
> > > > time
> > > > slot at the moment is Tuesday 12:30 JLab time.
> > > >
> > > > -Eugene
> > > >
> > > > ----- Original Message -----
> > > >> From: "Eugene Pasyuk" <pasyuk at jlab.org> > > >> To: "g8b run"
> > > >> <g8b_run at jlab.org> > > >> Sent: Tuesday, March 19, 2013
> > > >> 4:36:38 PM
> > > >> Subject: [G8b_run] Fwd: g8b TOF paddle issue
> > > >>
> > > >>
> > > >>
> > > >>
> > > >> ----- Forwarded Message -----
> > > >> From: "Eugene Pasyuk" <pasyuk at jlab.org> > > >> To: "Michael
> > > >> Dugger" <dugger at jlab.org> > > >> Cc: "Ken Livingston"
> > > >> <Kenneth.Livingston at glasgow.ac.uk> , "Franz
> > > >> Klein" <fklein at jlab.org> , "Brian Vernarsky"
> > > >> <soulish at gmail.com> ,
> > > >> "Volker Crede" <crede at fsu.edu> , "Patrick Collins"
> > > >> <pcollins at jlab.org> , "Charles Hanretty" <hanretty at jlab.org> >
> > > >> > >> Sent: Tuesday, March 19, 2013 4:21:10 PM
> > > >> Subject: Re: g8b TOF paddle issue
> > > >>
> > > >> Let's have a meeting. I set up doodle:
> > > >> http://doodle.com/ycqshd8fpnda66mx > > >>
> > > >> -Eugene
> > > >>
> > > >> ----- Original Message -----
> > > >>> From: "Michael Dugger" <dugger at jlab.org> > > >>> To: "Volker
> > > >>> Crede" <crede at fsu.edu> > > >>> Cc: "Ken Livingston"
> > > >>> <Kenneth.Livingston at glasgow.ac.uk> , "Franz
> > > >>> Klein" <fklein at jlab.org> , "Brian Vernarsky"
> > > >>> <soulish at gmail.com> , "Eugene Pasyuk" <pasyuk at jlab.org> > >
> > > >>> >>> Sent: Tuesday, March 19, 2013 3:36:51 PM
> > > >>> Subject: Re: g8b TOF paddle issue
> > > >>>
> > > >>>
> > > >>> Hi,
> > > >>>
> > > >>> This could be scary.
> > > >>>
> > > >>> From what I understand, this problem will create phi
> > > >>> dependent
> > > >>> inefficiencies. This will especially true for single track
> > > >>> events.
> > > >>> However,
> > > >>> if an analysis uses the data to self analyze the phi
> > > >>> dependent
> > > >>> efficiencies (e.g. forming quantities like (Y_PARA -
> > > >>> Y_PERP)/(Y_PARA
> > > >>> +
> > > >>> Y_PERP)), then the recooking of data will only help add
> > > >>> statistics
> > > >>> for
> > > >>> those type of analyses.
> > > >>>
> > > >>> Since I have two channels of g8b that have gone through
> > > >>> analysis
> > > >>> review,
> > > >>> and Volker is either finished with analysis review, or nearly
> > > >>> so,
> > > >>> it
> > > >>> is
> > > >>> important that we determine if those analysis can remain as
> > > >>> is.
> > > >>>
> > > >>> If it is determined that all of the analyses must use
> > > >>> recooked
> > > >>> data,
> > > >>> we
> > > >>> need to do the recooking as soon as possible.
> > > >>>
> > > >>> Take care,
> > > >>> Michael
> > > >>>
> > > >>> On Tue, 19 Mar 2013, Volker Crede wrote:
> > > >>>
> > > >>>> Hi all,
> > > >>>>
> > > >>>> It sounds really scary. Yes, we should meet and discuss
> > > >>>> this.
> > > >>>>
> > > >>>> Volker
> > > >>>>
> > > >>>>
> > > >>>> On Mar 19, 2013, at 12:34 PM, Michael Dugger
> > > >>>> <dugger at jlab.org> > > >>>> wrote:
> > > >>>>
> > > >>>>> Hi,
> > > >>>>>
> > > >>>>> Having a meeting makes sense.
> > > >>>>>
> > > >>>>> Take care,
> > > >>>>> Michael
> > > >>>>>
> > > >>>>> On Tue, 19 Mar 2013, Ken Livingston wrote:
> > > >>>>>
> > > >>>>>> Hi All,
> > > >>>>>> It does indeed look like we cooked with the version that
> > > >>>>>> was
> > > >>>>>> in
> > > >>>>>> /home/clasg8/g8/packages/
> > > >>>>>> where, as Brian says, we had
> > > >>>>>> #define SC_TDC_MAX 4096
> > > >>>>>>
> > > >>>>>> if I look at set_env_g8b.sh see
> > > >>>>>> export CLAS_PACK=/u/home/${RUN_USER}/g8/packages
> > > >>>>>>
> > > >>>>>> I think we do need to consider recalibrating the TOF and
> > > >>>>>> recooking the data. At least starting with one coherent
> > > >>>>>> peak
> > > >>>>>> setting.
> > > >>>>>>
> > > >>>>>> What do you all think?
> > > >>>>>> We should at least have a meeting to discuss this.
> > > >>>>>>
> > > >>>>>> Cheers,
> > > >>>>>> Ken
> > > >>>>>>
> > > >>>>>>
> > > >>>>>>
> > > >>>>>>
> > > >>>>>>
> > > >>>>>> On 19/03/13 13:43, Franz Klein wrote:
> > > >>>>>>> sorry, replied only to Eugene ...
> > > >>>>>>> ----- Forwarded Message -----
> > > >>>>>>> From: "Franz Klein" <fklein at jlab.org> > > >>>>>>> To:
> > > >>>>>>> "Eugene Pasyuk" <pasyuk at jlab.org> > > >>>>>>> Sent:
> > > >>>>>>> Tuesday, March 19, 2013 9:38:42 AM
> > > >>>>>>> Subject: Re: g8b TOF paddle issue
> > > >>>>>>> Yes, Eugene, I worked on the copy_pipeline.cc routine in
> > > >>>>>>> the
> > > >>>>>>> beginning of g9a ... mostly because the SC, EC banks took
> > > >>>>>>> the
> > > >>>>>>> first TDC entry from SCT, ECT instead of the one which is
> > > >>>>>>> in
> > > >>>>>>> the 'right' (expected) range.
> > > >>>>>>> So maybe I'll take a look first into the g8b version of
> > > >>>>>>> this
> > > >>>>>>> routine as well as SCT, ECT, REF.
> > > >>>>>>> ----- Original Message -----
> > > >>>>>>> From: "Eugene Pasyuk" <pasyuk at jlab.org> > > >>>>>>> To:
> > > >>>>>>> "Franz Klein" <fklein at jlab.org> > > >>>>>>> Cc: "Michael
> > > >>>>>>> Dugger" <dugger at jlab.org> , crede at fsu.edu ,
> > > >>>>>>> "Brian
> > > >>>>>>> Vernarsky" <soulish at gmail.com> , "Kenneth Livingston"
> > > >>>>>>> <Kenneth.Livingston at glasgow.ac.uk> > > >>>>>>> Sent:
> > > >>>>>>> Tuesday, March 19, 2013 9:29:45 AM
> > > >>>>>>> Subject: Re: g8b TOF paddle issue
> > > >>>>>>> One thing which comes to mind is that at some point after
> > > >>>>>>> pipeline TDC were installed we discovered that there is
> > > >>>>>>> some
> > > >>>>>>> issue in on-line procedure of matching TDC and ADC from
> > > >>>>>>> SC
> > > >>>>>>> and
> > > >>>>>>> SCT banks and remaking of raw SC bank. The procedure was
> > > >>>>>>> revisited and as I recall we used new matching procedure
> > > >>>>>>> in
> > > >>>>>>> user_ana for g9a data. May be this is the reason for g8b
> > > >>>>>>> problem?
> > > >>>>>>> -Eugene
> > > >>>>>>> ----- Original Message -----
> > > >>>>>>>> From: "Franz Klein" <fklein at jlab.org> > > >>>>>>>> To:
> > > >>>>>>>> "Kenneth Livingston"
> > > >>>>>>>> <Kenneth.Livingston at glasgow.ac.uk> > > >>>>>>>> Cc:
> > > >>>>>>>> "Michael Dugger" <dugger at jlab.org> , "Eugene Pasyuk"
> > > >>>>>>>> <pasyuk at jlab.org> , crede at fsu.edu , "Brian Vernarsky"
> > > >>>>>>>> <soulish at gmail.com> > > >>>>>>>> Sent: Tuesday, March
> > > >>>>>>>> 19, 2013 9:23:00 AM
> > > >>>>>>>> Subject: Re: g8b TOF paddle issue
> > > >>>>>>>> Ken,
> > > >>>>>>>> unfortunately I don't remember whether we checked or
> > > >>>>>>>> changed
> > > >>>>>>>> the cut
> > > >>>>>>>> on overflows. We took the code from eg3 (Joern) which
> > > >>>>>>>> assumes
> > > >>>>>>>> TDC
> > > >>>>>>>> entries in the range ~1000 to ~6000 (depending on
> > > >>>>>>>> particle
> > > >>>>>>>> and
> > > >>>>>>>> REF
> > > >>>>>>>> signal).
> > > >>>>>>>> However, Brian found out quite some time ago that often
> > > >>>>>>>> in
> > > >>>>>>>> multi-track events many track candidates weren't getting
> > > >>>>>>>> into
> > > >>>>>>>> time-based tracking due to missing timing information
> > > >>>>>>>> from
> > > >>>>>>>> ST
> > > >>>>>>>> and/or
> > > >>>>>>>> SC.
> > > >>>>>>>> For sure we made the mistake to cut out all SC paddles
> > > >>>>>>>> in
> > > >>>>>>>> the
> > > >>>>>>>> reconstruction for which the calibration didn't work out
> > > >>>>>>>> (instead of
> > > >>>>>>>> letting students worry about SC paddle cuts later in
> > > >>>>>>>> their
> > > >>>>>>>> analysis). In that sense it might be a good idea to
> > > >>>>>>>> recheck
> > > >>>>>>>> ST
> > > >>>>>>>> and
> > > >>>>>>>> SC calibrations and maybe rerun user_ana for some
> > > >>>>>>>> coh.edge
> > > >>>>>>>> setting
> > > >>>>>>>> on the farm.
> > > >>>>>>>> Maybe as a first step, Brian should tar his source code
> > > >>>>>>>> he
> > > >>>>>>>> copied
> > > >>>>>>>> from the clasg8 account and we verify whether it is the
> > > >>>>>>>> code
> > > >>>>>>>> which
> > > >>>>>>>> was used for g8b reconstruction.
> > > >>>>>>>> Cheers,
> > > >>>>>>>> Franz
> > > >>>>>>>> ----- Original Message -----
> > > >>>>>>>> From: "Ken Livingston"
> > > >>>>>>>> <Kenneth.Livingston at glasgow.ac.uk> > > >>>>>>>> To:
> > > >>>>>>>> "Brian Vernarsky" <soulish at gmail.com> > > >>>>>>>> Cc:
> > > >>>>>>>> "Michael Dugger" <dugger at jlab.org> , "Eugene Pasyuk"
> > > >>>>>>>> <pasyuk at jlab.org> , crede at fsu.edu , "Franz Klein"
> > > >>>>>>>> <fklein at jlab.org> > > >>>>>>>> Sent: Tuesday, March 19,
> > > >>>>>>>> 2013 8:18:45 AM
> > > >>>>>>>> Subject: Re: g8b TOF paddle issue
> > > >>>>>>>> Hi Brian,
> > > >>>>>>>> There's certainly something funny going on there which
> > > >>>>>>>> we
> > > >>>>>>>> need
> > > >>>>>>>> to get
> > > >>>>>>>> to
> > > >>>>>>>> the bottom of.
> > > >>>>>>>> However, I'm not sure your diagnosis is correct.
> > > >>>>>>>> As far as I can see, when I log on to the clasg8 account
> > > >>>>>>>> cd
> > > >>>>>>>> $CLAS_PACK
> > > >>>>>>>> directory is set to
> > > >>>>>>>> /home/clasg8/packages, not /home/clasg8/g8/packages/
> > > >>>>>>>> where
> > > >>>>>>>> you
> > > >>>>>>>> mention
> > > >>>>>>>> finding the header file with the old version of sc.h.
> > > >>>>>>>> In the clasg8 account version of $CLAS_PACK/include/sc.h
> > > >>>>>>>> the
> > > >>>>>>>> relevant
> > > >>>>>>>> line is
> > > >>>>>>>> #define SC_TDC_MAX 8192 /* pipeline */
> > > >>>>>>>> Do any of the rest of you have any opinion or memory on
> > > >>>>>>>> that?
> > > >>>>>>>> Regards,
> > > >>>>>>>> Ken
> > > >>>>>>>> On 18/03/13 22:03, Brian Vernarsky wrote:
> > > >>>>>>>>> Hello all,
> > > >>>>>>>>> In trying to finalize my results for the spin density
> > > >>>>>>>>> matrix
> > > >>>>>>>>> elements
> > > >>>>>>>>> for the omega I have run into a serious issue with the
> > > >>>>>>>>> g8b
> > > >>>>>>>>> dataset.
> > > >>>>>>>>> When I project out my spin density matrix elements I
> > > >>>>>>>>> found
> > > >>>>>>>>> that the
> > > >>>>>>>>> unpolarized elements, which can be compared to previous
> > > >>>>>>>>> experiments
> > > >>>>>>>>> (g11a most notably), were slightly offset with respect
> > > >>>>>>>>> to
> > > >>>>>>>>> those
> > > >>>>>>>>> previous measurements. I have shown these elements at
> > > >>>>>>>>> previous
> > > >>>>>>>>> CLAS
> > > >>>>>>>>> Hadron meetings so some of you may be aware of this.
> > > >>>>>>>>> I traced the source of my problem back to the fact that
> > > >>>>>>>>> the
> > > >>>>>>>>> phi
> > > >>>>>>>>> distributions of the particles were skewed and this was
> > > >>>>>>>>> not
> > > >>>>>>>>> properly
> > > >>>>>>>>> reflected in the monte carlo. Looking further into the
> > > >>>>>>>>> issue
> > > >>>>>>>>> I
> > > >>>>>>>>> discovered that the start counters have a serious issue
> > > >>>>>>>>> with
> > > >>>>>>>>> detecting
> > > >>>>>>>>> individual pions; the efficiency varies wildly from
> > > >>>>>>>>> paddle
> > > >>>>>>>>> to
> > > >>>>>>>>> paddle.
> > > >>>>>>>>> However, since we had a one-track trigger and I am
> > > >>>>>>>>> looking
> > > >>>>>>>>> for
> > > >>>>>>>>> three-track events with a proton, this was not the
> > > >>>>>>>>> source
> > > >>>>>>>>> of
> > > >>>>>>>>> my
> > > >>>>>>>>> issue,
> > > >>>>>>>>> however it could be a serious issue for anyone looking
> > > >>>>>>>>> into
> > > >>>>>>>>> single
> > > >>>>>>>>> pion reactions. The source of my issue is particles
> > > >>>>>>>>> that
> > > >>>>>>>>> have
> > > >>>>>>>>> a
> > > >>>>>>>>> TOF
> > > >>>>>>>>> paddle set to 0, indicating there is a problem with
> > > >>>>>>>>> them.
> > > >>>>>>>>> As
> > > >>>>>>>>> you
> > > >>>>>>>>> can
> > > >>>>>>>>> see in the enclosed file phi_distributions_g8b.pdf the
> > > >>>>>>>>> actual
> > > >>>>>>>>> phi
> > > >>>>>>>>> distribution for each particle (in black) looks to be
> > > >>>>>>>>> ok,
> > > >>>>>>>>> however
> > > >>>>>>>>> when
> > > >>>>>>>>> we remove the particles with TOF paddle = 0 (in red)
> > > >>>>>>>>> and
> > > >>>>>>>>> are
> > > >>>>>>>>> left
> > > >>>>>>>>> with
> > > >>>>>>>>> just the particles with a "good" TOF paddle (in blue)
> > > >>>>>>>>> there
> > > >>>>>>>>> is
> > > >>>>>>>>> a
> > > >>>>>>>>> pretty severe problem, mostly for the pions.
> > > >>>>>>>>> In looking at the TOF paddle = 0 events for the two
> > > >>>>>>>>> pions
> > > >>>>>>>>> you
> > > >>>>>>>>> can
> > > >>>>>>>>> notice that they are almost the exact same, whereas the
> > > >>>>>>>>> proton
> > > >>>>>>>>> has
> > > >>>>>>>>> significantly less events with a "bad" TOF paddle. And
> > > >>>>>>>>> there
> > > >>>>>>>>> is a
> > > >>>>>>>>> definite phi dependence to the bad events. Certainly
> > > >>>>>>>>> we
> > > >>>>>>>>> should
> > > >>>>>>>>> expect
> > > >>>>>>>>> some events with bad TOF paddles in every channel,
> > > >>>>>>>>> however
> > > >>>>>>>>> this is
> > > >>>>>>>>> accounting for almost half of the total events in
> > > >>>>>>>>> sector
> > > >>>>>>>>> 5
> > > >>>>>>>>> for
> > > >>>>>>>>> the
> > > >>>>>>>>> pions. There is no physical reason for this to be so.
> > > >>>>>>>>> I have found the source of the problem to be in the
> > > >>>>>>>>> TDCs
> > > >>>>>>>>> of
> > > >>>>>>>>> the TOF
> > > >>>>>>>>> paddles. In the file tdcs_and_adcs_g8b.pdf I have
> > > >>>>>>>>> shown
> > > >>>>>>>>> the
> > > >>>>>>>>> values
> > > >>>>>>>>> from the TDCs and ADCs for the TOF paddles, in the
> > > >>>>>>>>> order
> > > >>>>>>>>> TDCL,
> > > >>>>>>>>> ADCL,
> > > >>>>>>>>> TDCR, ADCR, for the proton (top), pi+ (middle) and pi-
> > > >>>>>>>>> (bottom),
> > > >>>>>>>>> integrated over all paddles and sectors for one
> > > >>>>>>>>> amorphous
> > > >>>>>>>>> run
> > > >>>>>>>>> (48133).
> > > >>>>>>>>> The blue on each plot are "good" events and the red
> > > >>>>>>>>> are
> > > >>>>>>>>> "bad", or
> > > >>>>>>>>> TOF
> > > >>>>>>>>> = 0, events. It is very evident from the TDC plots for
> > > >>>>>>>>> all
> > > >>>>>>>>> particles
> > > >>>>>>>>> that something turns on at channel 4096. I have tried
> > > >>>>>>>>> to
> > > >>>>>>>>> illustrate
> > > >>>>>>>>> that by drawing a vertical line at 4096 on the TDC
> > > >>>>>>>>> plots.
> > > >>>>>>>>> The
> > > >>>>>>>>> ADC
> > > >>>>>>>>> plots show nothing out of the ordinary.
> > > >>>>>>>>> What happened is that before the g8b run the TDCs were
> > > >>>>>>>>> changed
> > > >>>>>>>>> from
> > > >>>>>>>>> a
> > > >>>>>>>>> 12-bit system to a 16-bit system, changing the maximum
> > > >>>>>>>>> channel
> > > >>>>>>>>> from
> > > >>>>>>>>> 4096 to 65536. However, this change was not made in
> > > >>>>>>>>> the
> > > >>>>>>>>> code
> > > >>>>>>>>> as in
> > > >>>>>>>>> the g8b cooking code (found at
> > > >>>>>>>>> /home/clasg8/g8/packages/)
> > > >>>>>>>>> the
> > > >>>>>>>>> file
> > > >>>>>>>>> include/sc.h we find
> > > >>>>>>>>> #define SC_TDC_MAX 4096
> > > >>>>>>>>> instead of 8192 like we find in other experiments after
> > > >>>>>>>>> the
> > > >>>>>>>>> TDCs
> > > >>>>>>>>> were
> > > >>>>>>>>> changed. (It seems that while we effectively have
> > > >>>>>>>>> 65,536
> > > >>>>>>>>> channels
> > > >>>>>>>>> in
> > > >>>>>>>>> practice we only use 8192.) Any particle that
> > > >>>>>>>>> registered
> > > >>>>>>>>> above
> > > >>>>>>>>> 4096
> > > >>>>>>>>> on a TDC was deemed a "bad" event in that TDC. If the
> > > >>>>>>>>> particle had
> > > >>>>>>>>> a
> > > >>>>>>>>> "bad" TDCL but a "good" TDCR then it is still possible
> > > >>>>>>>>> to
> > > >>>>>>>>> recover
> > > >>>>>>>>> the
> > > >>>>>>>>> events, and vice versa, though not all particles could
> > > >>>>>>>>> be
> > > >>>>>>>>> recovered
> > > >>>>>>>>> in
> > > >>>>>>>>> this way. However, if both TDCs measured a value above
> > > >>>>>>>>> 4096
> > > >>>>>>>>> then
> > > >>>>>>>>> the
> > > >>>>>>>>> particle was deemed "bad" and assigned TOF paddle = 0.
> > > >>>>>>>>> For a signifcant number of TOF paddles the range of TDC
> > > >>>>>>>>> channels
> > > >>>>>>>>> was
> > > >>>>>>>>> from 3800-4200, though some skewed higher or lower than
> > > >>>>>>>>> others.
> > > >>>>>>>>> For
> > > >>>>>>>>> paddles where the distribution was quite high as many
> > > >>>>>>>>> as
> > > >>>>>>>>> half
> > > >>>>>>>>> of
> > > >>>>>>>>> the
> > > >>>>>>>>> pions were cut and a signficant number of protons were
> > > >>>>>>>>> also
> > > >>>>>>>>> cut.
> > > >>>>>>>>> This
> > > >>>>>>>>> led to difficulty in calibrating the paddle and so the
> > > >>>>>>>>> entire
> > > >>>>>>>>> paddle
> > > >>>>>>>>> was cut. There were 31 paddles cut in g8b, more than
> > > >>>>>>>>> 10%
> > > >>>>>>>>> of
> > > >>>>>>>>> the
> > > >>>>>>>>> total
> > > >>>>>>>>> number of paddles.
> > > >>>>>>>>> For the pions the cut is pretty evenly distributed
> > > >>>>>>>>> across
> > > >>>>>>>>> the
> > > >>>>>>>>> momentum
> > > >>>>>>>>> spectrum, but for protons it cuts only events above
> > > >>>>>>>>> ~550
> > > >>>>>>>>> MeV
> > > >>>>>>>>> as can
> > > >>>>>>>>> be
> > > >>>>>>>>> seen in the file p_dist_bad_paddles.pdf, which shows
> > > >>>>>>>>> the
> > > >>>>>>>>> momentum
> > > >>>>>>>>> distribution for protons that have been ascribed TOF
> > > >>>>>>>>> paddle
> > > >>>>>>>>> =
> > > >>>>>>>>> 0.
> > > >>>>>>>>> Now,
> > > >>>>>>>>> this is a small fraction of the total number of proton
> > > >>>>>>>>> events,
> > > >>>>>>>>> but
> > > >>>>>>>>> it
> > > >>>>>>>>> is still significant.
> > > >>>>>>>>> Based on all of this I think that it is imperative that
> > > >>>>>>>>> we
> > > >>>>>>>>> recook
> > > >>>>>>>>> the
> > > >>>>>>>>> g8b dataset. We will need to change the value of
> > > >>>>>>>>> SC_TDC_MAX
> > > >>>>>>>>> and
> > > >>>>>>>>> then
> > > >>>>>>>>> recalibrate the TOF paddles; hopefully the ones that
> > > >>>>>>>>> were
> > > >>>>>>>>> considered
> > > >>>>>>>>> "good" before will not need much work, but of the ones
> > > >>>>>>>>> considered
> > > >>>>>>>>> "bad" before most of them can almost certainly be
> > > >>>>>>>>> salvaged.
> > > >>>>>>>>> This
> > > >>>>>>>>> recook is necessary because it is clear that this is
> > > >>>>>>>>> significantly
> > > >>>>>>>>> affecting the phi and momentum distributions of all
> > > >>>>>>>>> particles
> > > >>>>>>>>> and
> > > >>>>>>>>> thus
> > > >>>>>>>>> will affect all measurements that depend on phi,
> > > >>>>>>>>> momentum,
> > > >>>>>>>>> TOF
> > > >>>>>>>>> or
> > > >>>>>>>>> particle ID. The plus side is that we can recover a
> > > >>>>>>>>> large
> > > >>>>>>>>> number
> > > >>>>>>>>> of
> > > >>>>>>>>> paddles and thus increase our statistics significantly,
> > > >>>>>>>>> especially
> > > >>>>>>>>> with multi-particle events. Any other minor issues
> > > >>>>>>>>> that
> > > >>>>>>>>> wouldn't
> > > >>>>>>>>> necessitate a recook on their own can also be addressed
> > > >>>>>>>>> before
> > > >>>>>>>>> we
> > > >>>>>>>>> start. And lastly I think that it would be a very good
> > > >>>>>>>>> idea
> > > >>>>>>>>> to
> > > >>>>>>>>> include some more banks in the cooked files this time
> > > >>>>>>>>> than
> > > >>>>>>>>> we
> > > >>>>>>>>> did
> > > >>>>>>>>> before; to find the TDC and ADC values I had to go to
> > > >>>>>>>>> the
> > > >>>>>>>>> raw
> > > >>>>>>>>> files
> > > >>>>>>>>> without any PID info and then cross check between that
> > > >>>>>>>>> and
> > > >>>>>>>>> the
> > > >>>>>>>>> cooked
> > > >>>>>>>>> file to make sure I had the right particle, certainly
> > > >>>>>>>>> the
> > > >>>>>>>>> SC
> > > >>>>>>>>> banks
> > > >>>>>>>>> should be included in the newly cooked files.
> > > >>>>>>>>> Let me know what you think, if you would like any
> > > >>>>>>>>> additional
> > > >>>>>>>>> information or plots just ask.
> > > >>>>>>>>> Brian
> > > >>>>>>>> --
> > > >>>>>>>> =======================================================
> > > >>>>>>>> Ken Livingston
> > > >>>>>>>> Dept. of Physics & Astronomy, Tel: +44 141 330
> > > >>>>>>>> 6428
> > > >>>>>>>> University of Glasgow, Fax: +44 141 330
> > > >>>>>>>> 5889
> > > >>>>>>>> Glasgow G12 8QQ.
> > > >>>>>>>> Scotland. UK.
> > > >>>>>>>> =======================================================
> > > >>>>>>>> --
> > > >>>>>>>> ===============================================================
> > > >>>>>>>> Franz J. Klein, Associate Professor
> > > >>>>>>>> CUA, Department of Physics
> > > >>>>>>>> Washington, DC 20064
> > > >>>>>>>> office: Hannan Hall 206 phone: 202-319-6190
> > > >>>>>>>> or: Jefferson Lab,CC F-243 phone: 757-269-6672
> > > >>>>>>>> ---------------------------------------------------------------
> > > >>>>>>
> > > >>>>>> --
> > > >>>>>> =======================================================
> > > >>>>>> Ken Livingston
> > > >>>>>>
> > > >>>>>> Dept. of Physics & Astronomy, Tel: +44 141 330 6428
> > > >>>>>> University of Glasgow, Fax: +44 141 330 5889
> > > >>>>>> Glasgow G12 8QQ.
> > > >>>>>> Scotland. UK.
> > > >>>>>> =======================================================
> > > >>>>
> > > >> _______________________________________________
> > > >> G8b_run mailing list
> > > >> G8b_run at jlab.org > > >>
> > > >> https://mailman.jlab.org/mailman/listinfo/g8b_run > > >>
> > > > _______________________________________________
> > > > G8b_run mailing list
> > > > G8b_run at jlab.org > > >
> > > > https://mailman.jlab.org/mailman/listinfo/g8b_run > >
> > >
> > > --
> > > =======================================================
> > > Ken Livingston
> > >
> > > Dept. of Physics & Astronomy, Tel: +44 141 330 6428
> > > University of Glasgow, Fax: +44 141 330 5889
> > > Glasgow G12 8QQ.
> > > Scotland. UK.
> > > =======================================================
> > >
> > > _______________________________________________
> > > G8b_run mailing list
> > > G8b_run at jlab.org > >
> > > https://mailman.jlab.org/mailman/listinfo/g8b_run > >
> > _______________________________________________
> > G8b_run mailing list
> > G8b_run at jlab.org >
> > https://mailman.jlab.org/mailman/listinfo/g8b_run >
> _______________________________________________
> G8b_run mailing list G8b_run at jlab.org
> https://mailman.jlab.org/mailman/listinfo/g8b_run
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