Freya Blekman
@freyablekman.bsky.social
Particle physicist at @CMSExperiment at @CERN - Lead Scientist DESY & Professor of Physics University of Hamburg - World citizen ➡🇳🇱🇺🇸 🇬🇧🇨🇭🇧🇪🇩🇪
Posts: #physics #SciComm + academia/tech stuff + my opinions + summaries of #CMSpapers
Posts: #physics #SciComm + academia/tech stuff + my opinions + summaries of #CMSpapers
Pinned
Freya Blekman
@freyablekman.bsky.social
· Nov 19
Freya Blekman: on the particle pathway of big science – Physics World
Experimental physicist Freya Blekman talks to Tushna Commissariat about the joy of working on big science collaborations
physicsworld.com
You can read a lot more about me and my career in this physicsworld.com/a/freya-blek...
Finding bottom (or beauty, whatever floats your boat) quarks is super important at the LHC. This paper describes one of the cutting-edge machine learning algorithms that is really good at finding multiple b quarks really close to each other
arxiv.org/abs/2510.10228
arxiv.org/abs/2510.10228
November 25, 2025 at 1:03 PM
Finding bottom (or beauty, whatever floats your boat) quarks is super important at the LHC. This paper describes one of the cutting-edge machine learning algorithms that is really good at finding multiple b quarks really close to each other
arxiv.org/abs/2510.10228
arxiv.org/abs/2510.10228
The LHC recently collided oxygen ions, and this #CMSPaper shows that we see charged particle suppression , a telltale sign that these collisions are creating the quark gluon plasma: arxiv.org/abs/2510.09864
November 25, 2025 at 11:27 AM
The LHC recently collided oxygen ions, and this #CMSPaper shows that we see charged particle suppression , a telltale sign that these collisions are creating the quark gluon plasma: arxiv.org/abs/2510.09864
We don't see the decay of the Higgs boson to charm quarks (yet!), but it is also possible to measure the interaction of the Higgs boson with charm by studying those particles being produced together. This #CMSPaper studies that Higgs+charm signature (we don't see it yet): arxiv.org/abs/2508.14988
November 24, 2025 at 6:22 PM
We don't see the decay of the Higgs boson to charm quarks (yet!), but it is also possible to measure the interaction of the Higgs boson with charm by studying those particles being produced together. This #CMSPaper studies that Higgs+charm signature (we don't see it yet): arxiv.org/abs/2508.14988
This #CMSpaper looks again at a non-significant (but intriguing!) excess in signatures consistent with two unstable, unknown particles from a heavier source. This paper further compares to theory predictions explaining these four-jet events
arxiv.org/abs/2507.17884
arxiv.org/abs/2507.17884
November 24, 2025 at 1:03 PM
This #CMSpaper looks again at a non-significant (but intriguing!) excess in signatures consistent with two unstable, unknown particles from a heavier source. This paper further compares to theory predictions explaining these four-jet events
arxiv.org/abs/2507.17884
arxiv.org/abs/2507.17884
This #CMSPaper explores the excitation of three particles with a B quark and other quark, examining how they store extra energy beyond the ground state. It marks the first simultaneous measurement of these particles. This improves knowledge of particles that contain quarks arxiv.org/abs/2508.05820
November 23, 2025 at 6:22 PM
This #CMSPaper explores the excitation of three particles with a B quark and other quark, examining how they store extra energy beyond the ground state. It marks the first simultaneous measurement of these particles. This improves knowledge of particles that contain quarks arxiv.org/abs/2508.05820
Are there undiscovered particles that decay to a Higgs boson and something else? This #CMSPaper describes how we scanned the invariant mass spectrum, but did not find any signs (in very very few events, and this should be rare. We will do this again when we have more data) arxiv.org/abs/2508.11494
November 23, 2025 at 1:03 PM
Are there undiscovered particles that decay to a Higgs boson and something else? This #CMSPaper describes how we scanned the invariant mass spectrum, but did not find any signs (in very very few events, and this should be rare. We will do this again when we have more data) arxiv.org/abs/2508.11494
The LHC produces a large number of Z bosons. So it is worthwhile checking if some of them behave inconsistently with the standard model. This #CMSPaper measured that the chance that Z bosons decay to two different kinds of leptons is smaller than one in 10 million arxiv.org/abs/2508.07512
November 22, 2025 at 6:22 PM
The LHC produces a large number of Z bosons. So it is worthwhile checking if some of them behave inconsistently with the standard model. This #CMSPaper measured that the chance that Z bosons decay to two different kinds of leptons is smaller than one in 10 million arxiv.org/abs/2508.07512
Are there undiscovered particles (that are very light for LHC standard) produced in Higgs boson decays? This #CMSPaper describes how we look for them, but did not see any arxiv.org/abs/2508.06947
November 22, 2025 at 1:03 PM
Are there undiscovered particles (that are very light for LHC standard) produced in Higgs boson decays? This #CMSPaper describes how we look for them, but did not see any arxiv.org/abs/2508.06947
Our summer students (and friends) are right: particle physics summer student programs are among the bucket-list activities for physics students. Registration for next summer opens now, and typically closes late January.
For your convenience, here are some links for the programs world-wide:
For your convenience, here are some links for the programs world-wide:
November 21, 2025 at 3:05 PM
Our summer students (and friends) are right: particle physics summer student programs are among the bucket-list activities for physics students. Registration for next summer opens now, and typically closes late January.
For your convenience, here are some links for the programs world-wide:
For your convenience, here are some links for the programs world-wide:
Are there invisible (and long-lived) undiscovered particles produced in the decays of B mesons? Those would be super rare, so we use a huge dataset of B mesons with dedicated data taking techniques. We didn't see any new particles though, this #CMSPaper is a #nullresult arxiv.org/abs/2508.06363
November 21, 2025 at 1:03 PM
Are there invisible (and long-lived) undiscovered particles produced in the decays of B mesons? Those would be super rare, so we use a huge dataset of B mesons with dedicated data taking techniques. We didn't see any new particles though, this #CMSPaper is a #nullresult arxiv.org/abs/2508.06363
If you need a reference model of what an extension of the standard model with many new particles would look like, Supersymmetry is a good benchmark. This #CMSPaper shows a general search in many standard signatures, looking for deviations spread over different signatures arxiv.org/abs/2508.13900
November 21, 2025 at 11:27 AM
If you need a reference model of what an extension of the standard model with many new particles would look like, Supersymmetry is a good benchmark. This #CMSPaper shows a general search in many standard signatures, looking for deviations spread over different signatures arxiv.org/abs/2508.13900
Every year in november, I make a little video summarising our group in Hamburg. We do such awesome stuff!
Enjoy this year's video 📽️ 💪 🤩 🤓
Enjoy this year's video 📽️ 💪 🤩 🤓
November 20, 2025 at 1:03 PM
Every year in november, I make a little video summarising our group in Hamburg. We do such awesome stuff!
Enjoy this year's video 📽️ 💪 🤩 🤓
Enjoy this year's video 📽️ 💪 🤩 🤓
Reposted by Freya Blekman
Ich freue mich auf einen Thread, in dem die schlechtesten Marketingideen von deutschen Universitäten aufgelistet sind. Bewohner:innen des deutschsprachigen Internets, bitte hier aktiv werden:
November 17, 2025 at 12:54 PM
Ich freue mich auf einen Thread, in dem die schlechtesten Marketingideen von deutschen Universitäten aufgelistet sind. Bewohner:innen des deutschsprachigen Internets, bitte hier aktiv werden:
And off to The Hague for a talk on particle physics!
November 17, 2025 at 2:25 PM
And off to The Hague for a talk on particle physics!
We don't see the decay of the Higgs boson to charm quarks (yet!), but it is also possible to measure the interaction of the Higgs boson with charm by studying those particles being produced together. This #CMSPaper studies that Higgs+charm signature (we don't see it yet): arxiv.org/abs/2508.14988
November 9, 2025 at 6:22 PM
We don't see the decay of the Higgs boson to charm quarks (yet!), but it is also possible to measure the interaction of the Higgs boson with charm by studying those particles being produced together. This #CMSPaper studies that Higgs+charm signature (we don't see it yet): arxiv.org/abs/2508.14988
This #CMSpaper looks again at a non-significant (but intriguing!) excess in signatures consistent with two unstable, unknown particles from a heavier source. This paper further compares to theory predictions explaining these four-jet events
arxiv.org/abs/2507.17884
arxiv.org/abs/2507.17884
November 9, 2025 at 1:03 PM
This #CMSpaper looks again at a non-significant (but intriguing!) excess in signatures consistent with two unstable, unknown particles from a heavier source. This paper further compares to theory predictions explaining these four-jet events
arxiv.org/abs/2507.17884
arxiv.org/abs/2507.17884
This #CMSPaper explores the excitation of three particles with a B quark and other quark, examining how they store extra energy beyond the ground state. It marks the first simultaneous measurement of these particles. This improves knowledge of particles that contain quarks arxiv.org/abs/2508.05820
November 8, 2025 at 6:22 PM
This #CMSPaper explores the excitation of three particles with a B quark and other quark, examining how they store extra energy beyond the ground state. It marks the first simultaneous measurement of these particles. This improves knowledge of particles that contain quarks arxiv.org/abs/2508.05820
Are there undiscovered particles that decay to a Higgs boson and something else? This #CMSPaper describes how we scanned the invariant mass spectrum, but did not find any signs (in very very few events, and this should be rare. We will do this again when we have more data) arxiv.org/abs/2508.11494
November 8, 2025 at 1:03 PM
Are there undiscovered particles that decay to a Higgs boson and something else? This #CMSPaper describes how we scanned the invariant mass spectrum, but did not find any signs (in very very few events, and this should be rare. We will do this again when we have more data) arxiv.org/abs/2508.11494
The LHC produces a large number of Z bosons. So it is worthwhile checking if some of them behave inconsistently with the standard model. This #CMSPaper measured that the chance that Z bosons decay to two different kinds of leptons is smaller than one in 10 million arxiv.org/abs/2508.07512
November 7, 2025 at 1:03 PM
The LHC produces a large number of Z bosons. So it is worthwhile checking if some of them behave inconsistently with the standard model. This #CMSPaper measured that the chance that Z bosons decay to two different kinds of leptons is smaller than one in 10 million arxiv.org/abs/2508.07512
Are there undiscovered particles (that are very light for LHC standard) produced in Higgs boson decays? This #CMSPaper describes how we look for them, but did not see any arxiv.org/abs/2508.06947
November 7, 2025 at 11:27 AM
Are there undiscovered particles (that are very light for LHC standard) produced in Higgs boson decays? This #CMSPaper describes how we look for them, but did not see any arxiv.org/abs/2508.06947
Congrats to Joel, he's great and this prize is super well deserved!
Huge congratulations to former CMS Spokesperson Joel Butler, recipient of the 2026 APS Panofsky Prize in Experimental Particle Physics! 👏
➡ Read more: cms.cern/news/cms-phy...
➡ Read more: cms.cern/news/cms-phy...
November 6, 2025 at 9:04 PM
Congrats to Joel, he's great and this prize is super well deserved!
Are there invisible (and long-lived) undiscovered particles produced in the decays of B mesons? Those would be super rare, so we use a huge dataset of B mesons with dedicated data taking techniques. We didn't see any new particles though, this #CMSPaper is a #nullresult arxiv.org/abs/2508.06363
November 6, 2025 at 6:22 PM
Are there invisible (and long-lived) undiscovered particles produced in the decays of B mesons? Those would be super rare, so we use a huge dataset of B mesons with dedicated data taking techniques. We didn't see any new particles though, this #CMSPaper is a #nullresult arxiv.org/abs/2508.06363
If you need a reference model of what an extension of the standard model with many new particles would look like, Supersymmetry is a good benchmark. This #CMSPaper shows a general search in many standard signatures, looking for deviations spread over different signatures arxiv.org/abs/2508.13900
November 6, 2025 at 1:03 PM
If you need a reference model of what an extension of the standard model with many new particles would look like, Supersymmetry is a good benchmark. This #CMSPaper shows a general search in many standard signatures, looking for deviations spread over different signatures arxiv.org/abs/2508.13900
Thank you Deutsche Bahn for delaying my train for 30 minutes after the Berlin public transport delayed me first by 40 minutes. Sigh. #silverlining
November 6, 2025 at 7:52 AM
Thank you Deutsche Bahn for delaying my train for 30 minutes after the Berlin public transport delayed me first by 40 minutes. Sigh. #silverlining
I learnt a lot today and so did the audience. Lifelong learning for everyone. On science for peace, and the power of big questions to achieve the impossible at cern 😇🤩
November 5, 2025 at 11:04 PM
I learnt a lot today and so did the audience. Lifelong learning for everyone. On science for peace, and the power of big questions to achieve the impossible at cern 😇🤩