WEBVTT 1 00:00:00.000 --> 00:00:01.310 Alessandra Pastore: You all know. 2 00:00:01.700 --> 00:00:19.890 Alessandra Pastore: are very high global warming potential gases with the high global warming potential on 100 a year time horizon. That is thousands time greater with respect to the one, the reference one that is Co. 2, that is, one. 3 00:00:20.260 --> 00:00:46.150 Alessandra Pastore: That means that since some years there is an effort in the in all the communities working on this kind of technology in order to find an alternative solutions, an alternative gas mixture that can be more eco-friendly than this. And without, let's say, losing in performance of the detector 4 00:00:46.220 --> 00:00:56.509 Alessandra Pastore: here, I just summarize a little bit, which is the status of the European gas regulation. As you know, the 1st one was released in 2,000 5 00:00:56.510 --> 00:01:21.330 Alessandra Pastore: 15, while it was revised and published last year. On the right. You can see, with respect also to the evolution, for example, of the Nhc. Rents concerning Cern, which is the goal of this new revision of the Fcas regulation. So the 1st goal is to redact by 6 00:01:21.410 --> 00:01:51.000 Alessandra Pastore: 55% greenhouse gases emission by 2030 with respect to the consumption of 1990. But the total elimination of hydrofluorocarbon is foreseen by 2050, and new restriction has been taken with respect to a larger list of high global warming potential gases and on the use of Sf, 6. So it is something that really touched 7 00:01:52.141 --> 00:01:58.309 Alessandra Pastore: in an important way, the use of this kind of detector. 8 00:01:58.320 --> 00:02:27.409 Alessandra Pastore: And on the bottom part of the slide I'm also reporting. But already it was discussed before, which is the cern objectives looking at the general framework. So the idea is to reduce that emission what is called scope, one of cern by 28%. This emission by the end of round 3 compared to the consumption of 2018, 9 00:02:27.410 --> 00:02:37.119 Alessandra Pastore: and the way to do this at the level of experiment is applying gas, recirculation, and recovery. This is already a reality, but in any case 10 00:02:37.410 --> 00:02:56.160 Alessandra Pastore: can be done in a more efficient way. In addition to the search of, as we were saying before, more eco-friendly alternatives to the gases, uses used in particle detection, not only on Rpcs, but also on a variety of other gases. Detector used in particle physics. 11 00:02:56.941 --> 00:03:18.640 Alessandra Pastore: Since 2,019, the Rpc plus plus collaboration. That is a joint effort in between different communities working on Rpcs is, I started hard in order to find at 1st a complete alternative to twitter for retain. 12 00:03:18.640 --> 00:03:36.270 Alessandra Pastore: So a 1st solution from our side is a substitution of the overall quantity overall fraction of data for retaining with a mixture of data for propane and Co. 2, which are both low global warming potential gases. 13 00:03:36.270 --> 00:03:53.700 Alessandra Pastore: and among the several gas mixers tested with their Pcs. 2 of them that are here highlighted in red, called echo 2 and eco. 3, as shown from the point of view of a physicist, to be very promising. So in terms of performance 14 00:03:53.920 --> 00:04:18.849 Alessandra Pastore: in particular, and now, in the last years, in the last 3 years, we started also to look at the performance of those mixture, looking at the longer term period, using them in an Rpc. The collaboration usually work in normal laboratories and with a common setup itself 15 00:04:18.850 --> 00:04:43.169 Alessandra Pastore: at the Gamma irradiation facility. Here there is a picture of the bunker. Inside the facility this facility provides gamma source with 13 terabycular activity, and the possibility to irradiate detector at different rates particle rates, in addition to a 9 beam that is very useful to 16 00:04:43.170 --> 00:05:01.939 Alessandra Pastore: performance of the detector. Also, after some period of aging with the alternative gas mixer in the table, you can see in summary the setup of the collaboration. So there are different Pcs with different layout and without plays, that 17 00:05:02.040 --> 00:05:26.979 Alessandra Pastore: 3 and 6 meter distance with respect to the source, and we compare results, or together, looking at the dose delivered at the detector. So the same dose delivered to the detector instead of the nominal abs. Let's say that is applied inside the gif plus plus to have compatible compatibility between the the results. Here there is the roadmap 18 00:05:26.980 --> 00:05:44.059 Alessandra Pastore: of the collaboration, so in summary. It is a systematic work in which we started in July 2,022, with the 1st beam test at Gif plus plus. To assess the performance. Baseline of our detector with standard mixes, but we already knows. 19 00:05:44.060 --> 00:06:07.450 Alessandra Pastore: and with echo 2 and eco. 3. Mixture. Then every year, during spring and summer we perform beam tests to verify the status of the performance of the detector after aging campaign that consists in operating Pcs. With the echo. 2 mixture at gifpl 20 00:06:07.450 --> 00:06:31.850 Alessandra Pastore: give plus plus. So after irradiation at a specific abs 2.2, that means a very high irradiation. In order to understand if this molecule. Friendly mixture can work also on a long term period, and, moreover, in again, systematically, we check resistivity and integrated charge because are key quantities. In looking at this aspect. 21 00:06:32.190 --> 00:06:51.430 Alessandra Pastore: So here there is a summary of the baseline performance that we obtained in 2022. If you are curious about all the details, you can have a look at the papers that we published that are linked here. But briefly here I'm showing the distribution of charge 22 00:06:51.430 --> 00:07:09.599 Alessandra Pastore: for one of the detectors the address at working point. It's clear that in case of the eco-friendly mixture echo 2 and eco 3, the fraction of events with high charge. Deliver this picker, and is higher as the fraction of Co. 2 increase in the mixture. 23 00:07:09.610 --> 00:07:34.570 Alessandra Pastore: While we do not see any difference in between the 3. Mix in terms of mean cluster size in each layout. Let's say we are considering while we see some differences in performance, but at the level of 1, 2%. If we look at source of sono irrigation 24 00:07:34.570 --> 00:07:59.080 Alessandra Pastore: in between standard gas mixture and the eco-friendly mixture, so it's something that is well accepted possible in the future to be used. If we look at high radiation condition, we see a degradation of these performances that is at the level of 2, 3% for the standard gas mixture and reach level 25 00:07:59.080 --> 00:08:00.480 Alessandra Pastore: 10% 26 00:08:00.480 --> 00:08:21.330 Alessandra Pastore: for the Eco mixture. So again, in this case, it's a matter of choice of the collaboration eventually to lose some fraction and some percent in efficiency, maybe taking into account more detector with respect to one. In order to get in any case the physics results. 27 00:08:21.440 --> 00:08:44.879 Alessandra Pastore: So, as said before, the aging campaign started in August 22. Here you can see the status of the art of the charge, that density that has been integrated by the old detector. So the majority of the detector reached the level of the of 700 of microcoulomb per centimeter squared. In some cases it's the target for the future application. 28 00:08:44.920 --> 00:09:09.719 Alessandra Pastore: From the point of view of resistivity we do not have seen a clear increase of these key quantities that can be a sign of aging of the detector. Even in this case we have some issue. But now it's recovered after a particular treatment of the detector itself, and this monitoring is done every 2, 3 times a year for 29 00:09:09.720 --> 00:09:20.550 Alessandra Pastore: for each, for each detector in terms of performances. Here I'm reporting the results of the systematic beam test we are we are doing on the left. 30 00:09:20.620 --> 00:09:32.800 Alessandra Pastore: There are results for one of the detectors that are, let's say, similar to what we see with the others, one here at source, so no irradiation 31 00:09:32.800 --> 00:09:57.730 Alessandra Pastore: for the standard mix and the echo, 2 echo dust mixture we see clearly starting from 2022 up to 2024. So, having integrated them around 300 minicoulomb per centimeter square with this detector that there is a clear shift of the high voltage we have to apply to the detector to be efficient. 32 00:09:57.730 --> 00:10:19.540 Alessandra Pastore: but in any case the efficiency of the detector is still there. There is a little bit of degradation, as I've seen for the eco mixture. But it's something affordable, while we see clearly an increase of current density absorbed by the detector that is at the same level, we have to say in between standard mixture and deco 2. 33 00:10:19.540 --> 00:10:43.350 Alessandra Pastore: So from the point of view of operation at source software, it seems that the performance are stable also after long term. If we and this is true also, if we consider, let's say, middle rate application. If we go to very high risk. Here there are superimposed several distribution for standard mixture echo 2 and echo 3, 34 00:10:43.350 --> 00:10:53.770 Alessandra Pastore: and for 2,002. So the baseline, 2,003 and 2,004 in summary. What we see is again a shift in the working point of the detector. 35 00:10:53.770 --> 00:11:04.819 Alessandra Pastore: and some degradation for the test beam. In 2024 of the efficiency value that we can reach. 36 00:11:05.385 --> 00:11:22.299 Alessandra Pastore: So this is, let's say, sign that this kind of mixer can be a solution, but not in, let's say, at every particle ray to to which the detector is exposed. 37 00:11:22.570 --> 00:11:51.390 Alessandra Pastore: So concluding recipe chamber detector are usually created with the high performance high global warming potential gas mixture, the standard one that is based on tetrafluoretane and Sf. 6. Since 2019 there is a specific harder and the ongoing in order to look at alternatives with respect to the standard mixture without losing in performance. From the point of view of science. 38 00:11:51.600 --> 00:11:59.899 Alessandra Pastore: currently, alternatives have been found with the mix, let's say, of Tetraphopropane and Co. 2 39 00:11:59.900 --> 00:12:23.750 Alessandra Pastore: were selected and used to study, which is the long term performance of the detector operated in such a mixture, and after 3 years of aging campaign we have seen that this kind of mixer in particular, echo 2 can be suitable for mid-rate application, and a good compromise at Lhc. 40 00:12:23.750 --> 00:12:37.310 Alessandra Pastore: But it cannot be the optimal choice for very high rate application from the point of view of physics. That's why a new R. And D phase is in the pipeline for us with 2 goals. 41 00:12:37.500 --> 00:12:53.610 Alessandra Pastore: So the 1st one is to find something alternative that can be used at very high rate applications. So in several application in the future, and that is also sf, 6, free and potential, free also from fast 42 00:12:53.630 --> 00:13:11.550 Alessandra Pastore: component, like H of 4, is looking more at the natural components, let's say, going a little bit back from this point of view, and being more friendly, let's say, with respect to environment, that's all. 43 00:13:14.090 --> 00:13:22.717 Yann Coadou: Thank you, Alison, so we have a bit eaten up into the question time so unless there is an urgent question 44 00:13:23.570 --> 00:13:32.010 Yann Coadou: I suggest to move on to the next talk. I don't see any raised hands. But it it's good that you're 45 00:13:32.170 --> 00:13:37.439 Yann Coadou: developing this and having also plans yeah, going for high rate applications. 46 00:13:37.440 --> 00:13:49.500 Alessandra Pastore: I. I have to say that even when collaboration, and in this case there is an effort that is transversal to several collaboration work on this item. 47 00:13:49.500 --> 00:14:08.680 Alessandra Pastore: It's in any case difficult to get funds. So I would say, this is a crucial point, really, really. So it's true that it's difficult to arrive to collaboration. But even if you arrive, collaboration in themselves have some difficulties to find to catch funds for this kind of 48 00:14:08.680 --> 00:14:11.830 Alessandra Pastore: still have difficulties. Unfortunately. 49 00:14:13.770 --> 00:14:14.869 Yann Coadou: Okay, so. 50 00:14:15.070 --> 00:14:16.040 Alessandra Pastore: Thank you. 51 00:14:16.040 --> 00:14:17.033 Yann Coadou: Thank you. 52 00:14:18.750 --> 00:14:22.439 Yann Coadou: So now our next speaker is Rodimir. 53 00:14:22.550 --> 00:14:24.309 Yann Coadou: Can you share your slides? 54 00:14:24.910 --> 00:14:25.540 Volodymyr Svintozelskyi: Yeah.