During 47 Congress of Polish Physicists, a probe with CosmicWatch detectors was sent into the stratosphere

47 Con­gress of Polish Phy­si­ci­sts takes place in Byd­goszcz on 19–23 Sep­tem­ber 2021. On Sep­tem­ber 19, the part of the Con­gress dedi­ca­ted to teaching phy­sics was inau­gu­ra­ted by sen­ding a tan­dem stra­to­sphe­ric probe, which inc­lu­ded cosmic rays detec­tors pro­vi­ded by NCBJ.

The stra­to­sphe­ric mis­sion BHR-21 (Byd­goszcz-Her­ge­sel-Rege­ner) began at noon from the old Mar­ket Squ­are in Byd­goszcz. For the first time in Poland a tan­dem bal­loon probe was used, which was repli­ca­ting histo­ric methods inven­ted and prac­ti­ced by XIX cen­tury scien­ti­sts, Hugo Her­ge­sel and Erich Rege­ner, both of Byd­goszcz ori­gin. The mis­sion goal was to measure the flux of cosmic radia­tion which was a spe­cialty of Erich Rege­ner. The place of start was care­fully selec­ted as well, the 18 meri­dian honors Marian Rejew­ski, mathe­ma­ti­cian and cryp­to­lo­gist from Byd­goszcz. To ensure the safety of the mis­sion, the probe was equ­ip­ped with mul­ti­ple inde­pen­dent tele­me­tric sys­tems which allo­wed the mis­sion orga­ni­sers to con­stan­tly moni­tor its posi­tion and quic­kly locate it after the lan­ding.

As it some­ti­mes hap­pens with scien­ti­fic expe­ri­ments, not eve­ry­thing went accor­ding to the plan of the mis­sion orga­ni­sers. The buoy­ancy force of one of the bal­lo­ons, tac­ting as a para­chute during the descent, was too low and right after the start it was pla­ced at the bot­tom of the probe. After the main bal­loon burst at 20 km above the gro­und, the second bal­loon was entan­gled in the rig­ging as well as emer­gency para­chutes and the pla­ce­ment of all the cap­su­les was inver­ted. For­tu­na­tely, the mis­sion lan­ded on a fre­shly plo­wed field and despite the rough cha­rac­ter of the lan­ding, none of the elec­tro­nic or optic equ­ip­ment Was dama­ged.

The detec­tors of cosmic radia­tion used in this mis­sion were a set of two Cosmi­cWatch coun­ters. These devi­ces, desi­gned as a part of an edu­ca­tio­nal pro­ject between NCBJ and MIT, work based on a pla­stic scin­til­la­tor and sili­con pho­to­mul­ti­plier (SiPM). The device can regi­ster impul­ses cau­sed by char­ged ioni­sing par­tic­les pas­sing thro­ugh the scin­til­la­tor and in result measure their quan­tity. In order to measure cosmic radia­tion, one must cre­ate a setup using two Cosmi­cWatch detec­tors and take coin­ci­dent measu­re­ments. In this method, one of the detec­tors regi­sters only those impul­ses that are also detec­ted by the second device. This way we mostly measure muons and ignore elec­trons and gamma radia­tion. This kind of expe­ri­ment aims to demon­strate the way in which the num­ber of detec­ted muons chan­ges with alti­tude.

NCBJ scien­ti­sts have alre­ady sent Cosmi­cWatch detec­tors to the stra­to­sphere, as a part of the Near Space 2018 con­fe­rence in Toruń. A simi­lar set of two Cosmi­cWatch detec­tors reached the alti­tude of 32 km (Scien­ti­sts from NCBJ sent edu­ca­tio­nal detec­tors in near outer space | Natio­nal Cen­tre for Nuc­lear Rese­arch).

Addi­tio­nal infor­ma­tion

47th Con­gress of Polish Phy­si­ci­sts Was orga­ni­sed by Polish Phy­si­cal Society, Byd­goszcz Uni­ver­sity of Science and Tech­no­logy, Ludwik Rydy­gier Col­le­gium Medi­cum in Byd­goszcz and Kazi­mierz Wielki Uni­ver­sity. The event Was super­vi­sed by the Polish Phy­si­cal Society, depart­ment in Byd­goszcz.

The offi­cial inau­gu­ra­tion of the Con­gress of Polish Phy­si­ci­sts took place on Sep­tem­ber 20th. Among the guests were highly regar­ded scien­ti­sts, such as prof. Frank Wil­czek, a Nobel Prize win­ner of polish ori­gin, who gave a lec­ture on time cry­stals. Other guests inc­lu­ded e. g. prof. Luc Bergé, the Pre­si­dent of Euro­pean Phy­si­cal Society and Anna Zie­liń­ska, the grand­dau­gh­ter of the world-renown che­mist and metal­lur­gist Jan Czo­ch­ral­ski, the inven­tor of a method of mono­cry­stal growth that is widely used to this day. On Mon­day, Sep­tem­ber 20, ano­ther stra­to­sphe­ric mis­sion was laun­ched, this time focu­sed on mete­oro­lo­gi­cal measu­re­ments. Simi­lar to the pre­vious day, before the mis­sion start there were exten­sive pre­pa­ra­tions accom­pa­nied by signi­fi­cant com­men­tary for the audience. The pro­ces­sed data from both mis­sions will be publi­shed on the inter­net in the form of video recor­dings. This way the inte­re­sted vie­wers will be able to expe­rience the entire fli­ght, all while mani­pu­la­ting the camera view, thro­ugh the use of high-reso­lu­tion sphe­ri­cal came­ras. More infor­ma­tion will be posted on the Con­gress of Polish Phy­si­ci­sts website (47 Zjazd Fizy­ków Pol­skich PTF (utp. edu. pl) ).

The Sun­day ses­sion, the ope­ning cere­mony as well as ple­nary lec­tures were live­stre­amed thro­ugh YouTube and are ava­ila­ble on the Con­gress’ chan­nels: 47 Zjazd Fizy­ków Pol­skich – YouTube, 47 Zjazd Fizy­ków Pol­skich CM UMK – YouTube.