The traditional informal meeting with PhD students and supervisors will take place on Friday, October 11, at 14.00 (A945 or will be specified later).

In 2019 Shusterman et al. published in Nature [1] their measurement of neutron capture cross section of 88Zr. The result of 861 kb means that this is the second-largest thermal neutron capture cross-section ever measured. Two years later, authors also reported a huge resonance integral of 2.530 Mb [2], which is in fact the surprising result for the nuclear physics community. As such, it further strengthened the sparked interest. Recently, the neutron capture cross-section was measured at two time-of-flight facilities, namely using the DICER instrument at LANSCE in LANL, and at the n_TOF facility in CERN. Most importantly, the DICER result [3] on the resonance integral disputes the Shusterman’s. I would like to briefly describe the techniques, present the results, and discuss why the DICER values are more “natural” considering the statistical model of nucleus. If available and possible, I will also show the status of the n_TOF measurement.

The meeting with students takes place on Monday September 30 at 12.20 in the A945 room (big lecture room on the 9th floor). All interested ones in the study of the Particle and Nuclear Physics branch are kindly invited. The meeting will be held in Czech a meeting with a non-Czech speaking students will be organized separately.

The lecture “Fyzika elementárních částic” (NJSF105) will start after the meeting, likely at about 1 PM.

Results

je naplánován na pátek 7. 6. 2024 odpoledne (od cca 14 hod.)

There’s been a partial change of route. Due to the kayak World Cup, we cannot run along the usual route on the return along the river, but we have to go “inland”, which induces a slight extension (to 7.2 km).

Hopefully, the final route plan (thanks to Franciszek!) is here:
https://en.mapy.cz/s/fefedepoce

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The meeting with students takes place on Monday February 19 at 12.20 in the A945 room (big lecture room on the 9th floor). All interested ones in the study of the Particle and Nuclear Physics program are kindly invited. Information in English will be given individually, the meeting is planned in Czech.

The first (not necessarily final) version of time-tables is available at

• Time-table for the 3rd year Bc. students [cz]
• Time-table for the 1st year MSc. students [cz]

Please note, that the current e-mail server (ipnp.mff.cuni.cz) is being discontinued by the end of February 2024. After this date, emails addressed to the old mailbox will be forwarded, but you can no longer access the old mailbox. All university employees have access to the central mail server (matfyz.cuni.cz) which can (should) be used as a replacement. If you wish to transfer your old e-mails from the old mailbox (ipnp.mff.cuni.cz) to the new one (matfyz.cuni.cz), please follow the instructions from this page.

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The usual approach to instantons via the homotopy classification of the gauge-potential configurations actually points to the non-trivial topology of the underlying geometrical object, namely the twisted principal or associated vector fiber bundle. And since the twisted fiber bundle also manifests itself by various anomalies, it points to the non-trivial topology of yet another geometrical object, the fiber bundle over the gauge-potential moduli space, with the BRST operator and the FP ghosts given by the projection of the variational operator onto the fiber of gauge transformations. The reduction of this fiber bundle over the moduli space to 1+1 dimension, in which the remaining moduli space dimension is the one used in Poincare lemma in the specific form of  the Cartan homotopy operator giving the Chern-Simons form of the appropriate Chern character and the second dimension (coming from fiber dimensions) is compactified to a loop, gives the construction of the non-abelian anomaly from the abelian one at 2 dimensions higher and from the spectral flow at the dimension in between. The whole bundle over the moduli space without restriction or compactification of its infinitely many functional-space directions might have (speculation) further topological features.