[Rivet] thrustMinor returns zero while calculating transverse thrust

[Deepak Kar]

Hi Holger,

Thanks, that is very helpful to know. Since many of us now calculating
transverse quantities, may be it will be useful to add these methods
more clearly?

Cheers,
Deepak

On Thu, Nov 21, 2013 at 4:50 PM, Holger Schulz
<hschulz at physik.hu-berlin.de> wrote:
> Hi Deepak,
>
> in the transverse case you get Thrust minor by asking
> the thrust projection for major:
>
> double minor  = thrust.thrustMajor();
>
> Cheers,
> Holger
>
> On 21/11/13 16:39, Deepak Kar wrote:
>> Hi,
>>
>> We are trying to finalize the Rivet analysis for arXiv:1207.6915
>> (ATLAS charged particle event shape).
>> A previous version of the data values is already in HepData, which
>> needs an update (more [lots were addded, systematics reduced following
>> referee review). Also a previous version of the analysis was written
>> (but never validated), but it seemed to work. However, with rivet
>> 1.8.3, thrustMinor returns zero, however thrustMajor gives non-zero
>> values. The relevant part of the code:
>>
>>
>>  // Loop over particles
>>        foreach (const Particle& p, particles500) {
>>          num500 += 1;
>>          ptSum500 += p.momentum().pT()/GeV;
>>
>>          // Transverse Thrust calculation requires p_z to be set to 0
>>          Vector3 mom = p.momentum().vector3();
>>          mom.setZ(0.0);
>>          momenta.push_back(mom);
>>        }
>>
>>
>>  // Actual Thrust calculation
>>       Thrust thrust;
>>       thrust.calc(momenta);
>>
>>       const double T  = 1.0 - thrust.thrust();
>>       const double TM = thrust.thrustMinor();
>>
>>
>> We will convert the code to 2.0.x once it is fixed.
>>
>> Thanks,
>> Deepak
>>
>



-- 
Deepak Kar
ATLAS Research Associate
University of Glasgow, UK.
Homepage: http://ppewww.physics.gla.ac.uk/~dkar/


Room 474, Kelvin Building.
Phone: (0044) 141 330 2599 (office), 0789 156 4318 (mobile)

While at CERN:
Building 1, R-019
Phone: (0041) 22-76-75950 (office), 0767321349 (mobile)

While at USA:
Phone: (001) 330-998-1500