[Clas_hadron] abstracts for DNP

Barry Ritchie Barry.Ritchie at asu.edu
Fri Jun 28 12:54:24 EDT 2013 

So maybe it would be better to go ahead and have the opening sentence speak about "exclusive eta photoproduction on the proton", which then would not need the qualifier about "one-step excitation". "Generic" eta photoproduction can be inclusive, so saying exclusive cleans that up. As Mike indicates, we only discuss exclusive production in the abstract.

Barry G. Ritchie 
Vice Provost for Academic Personnel 
Arizona State University 
300 E. University Ave, Suite 420 
Tempe, AZ 85287-7805 
 
Phone: 480-965-7405 
Fax: 480-965-0785


-----Original Message-----
From: Viktor Mokeev [mailto:mokeev at jlab.org] 
Sent: Friday, June 28, 2013 9:43 AM
To: Barry Ritchie
Cc: clas hadron; Michael Dugger; Eugene Pasyuk
Subject: Re: [Clas_hadron] abstracts for DNP

  Dear Barry,

 It is true, but this problem should be resolved in the selection of exclusive events and related corrections for exclusive cross sections should be incorporated.

  Best Regards,
                         Victor

----- Original Message -----
From: "Barry Ritchie" <Barry.Ritchie at asu.edu>
To: "Michael Dugger" <michael.dugger at asu.edu>, "Eugene Pasyuk" <pasyuk at jlab.org>
Cc: "clas hadron" <clas_hadron at jlab.org>
Sent: Friday, June 28, 2013 12:33:20 PM
Subject: Re: [Clas_hadron] abstracts for DNP

But we could have an undetected pion flying around, though, in the 2pi steradians CLAS doesn't cover. 

Barry G. Ritchie 
Vice Provost for Academic Personnel 
Arizona State University 
300 E. University Ave, Suite 420 
Tempe, AZ 85287-7805 
 
Phone: 480-965-7405 
Fax: 480-965-0785


-----Original Message-----
From: clas_hadron-bounces at jlab.org [mailto:clas_hadron-bounces at jlab.org] On Behalf Of Michael Dugger
Sent: Friday, June 28, 2013 9:26 AM
To: Eugene Pasyuk
Cc: clas hadron
Subject: Re: [Clas_hadron] abstracts for DNP


Hi,

Since we have the final state as
p eta,
we can't have an extra pion flying about. We can probably safely remove the "in one-step excitation processes" part.

Take care,
Michael

On Fri, 28 Jun 2013, Eugene Pasyuk wrote:

> Igor,
>
> As alternative to single step you may say that N\eta final state cannot be directly coupled to \Delta resonances.
>
> -Eugene
>
> ----- Original Message -----
>> From: "Igor Senderovich" <senderov at jlab.org>
>> To: "Viktor Mokeev" <mokeev at jlab.org>
>> Cc: "clas hadron" <clas_hadron at jlab.org>
>> Sent: Friday, June 28, 2013 5:07:33 PM
>> Subject: Re: [Clas_hadron] abstracts for DNP
>>
>> Dear Viktor,
>>
>> What I would call a two-step process is one in which the state 
>> de-excites via two emissions - say Delta excitation decaying with 
>> pion emission to an N* which then emits an eta. This illustrates a 
>> case when detection of an eta would not offer isospin filtering. I am 
>> just being careful to avoid such a counterexample to my statement.
>>
>> All the best,
>> -Igor
>>
>>
>> ----- Original Message -----
>> From: "Viktor Mokeev" <mokeev at jlab.org>
>> To: "Igor Senderovich" <senderov at jlab.org>
>> Cc: "clas hadron" <clas_hadron at jlab.org>
>> Sent: Thursday, June 27, 2013 4:55:15 PM
>> Subject: Re: [Clas_hadron] abstracts for DNP
>>
>>   Dear Igor,
>>
>>  You abstracts look good.
>>
>>  Could you explain what you mean by one-step excitation processes?
>>
>>  Best Regards,
>>                       Victor
>>
>> ----- Original Message -----
>> From: "Igor Senderovich" <senderov at jlab.org>
>> To: "clas hadron" <clas_hadron at jlab.org>
>> Sent: Thursday, June 27, 2013 11:30:15 AM
>> Subject: [Clas_hadron] abstracts for DNP
>>
>> Dear Colleagues,
>>
>> I would like to submit the two abstracts that follow this e-mail for 
>> the meeting of the DNP and appreciate any feedback you can offer.
>> Best regards,
>> -Igor Senderovich
>>
>> ----------
>> For the mini-symposium (14e. Mini-Symposium on the Excited Nucleon 
>> State Spectrum and Structure):
>> Title: Studies of $\eta$ photo-production in the baryon resonance 
>> excitation region with CLAS
>> Abstract:
>> Because the pseudoscalar $\eta$ meson has zero isospin, $\eta$ 
>> photo-production offers the feature of isolating N* (I=1/2) resonance 
>> states in one-step excitation processes. This ``isospin''
>> filter property can be very useful in helping disentangle the broad 
>> and overlapping excitations that make up the nucleon resonance 
>> spectrum. For that reason, a program of measurements on $\eta$ 
>> photo-production for the reaction $\gamma p \rightarrow \eta p$ has 
>> been conducted using the Hall B CEBAF Large Acceptance Spectrometer 
>> at Jefferson Lab. Results for the differential cross-section and for
>> single- and double-polarization observables will be summarized. The 
>> general outlook for the ``complete experiment'' program for 
>> disentangling nucleon resonances decaying to the $p \eta$ channel 
>> will be discussed.
>>
>>
>> A general DNP submission:
>> Title: Double-polarization E and G observables in $\eta$ 
>> photo-production on the CLAS Frozen Spin Target
>> Abstract:
>> $\eta$ photo-production is an important tool in baryon spectroscopy, 
>> allowing isolation of N* (I=1/2) resonances in one-step excitation 
>> processes. Furthermore, it has long been recognized that due to 
>> significant overlapping of resonances in the baryon spectrum, 
>> differential cross-sections are not enough; measuring polarization 
>> observables is vital. Extensive data have been collected at Jefferson 
>> Lab in Hall B with circularly and linearly polarized tagged photon 
>> beams incident on longitudinally polarized protons provided by the 
>> Frozen Spin Target (FROST). The presentation will cover analysis and 
>> preliminary results of double-polarization observables E and G in 
>> $\eta$ photo-production - data entirely missing from the world 
>> database.
>> _______________________________________________
>> Clas_hadron mailing list
>> Clas_hadron at jlab.org
>> https://mailman.jlab.org/mailman/listinfo/clas_hadron
>> _______________________________________________
>> Clas_hadron mailing list
>> Clas_hadron at jlab.org
>> https://mailman.jlab.org/mailman/listinfo/clas_hadron
>>
> _______________________________________________
> Clas_hadron mailing list
> Clas_hadron at jlab.org
> https://mailman.jlab.org/mailman/listinfo/clas_hadron
>
_______________________________________________
Clas_hadron mailing list
Clas_hadron at jlab.org
https://mailman.jlab.org/mailman/listinfo/clas_hadron

_______________________________________________
Clas_hadron mailing list
Clas_hadron at jlab.org
https://mailman.jlab.org/mailman/listinfo/clas_hadron

More information about the Clas_hadron mailing list