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...
Reposted by Freya Blekman
This is how the massive steel structure for the new CMS calorimeter, HGCAL, was tested! 👷
Last summer the structure that will house the delicate HGCAL cassettes was assembled in Pakistan and rotated to test its integrity.
📽️ Watch the timelapse: youtu.be/Xs_RxGwwlC0
Last summer the structure that will house the delicate HGCAL cassettes was assembled in Pakistan and rotated to test its integrity.
📽️ Watch the timelapse: youtu.be/Xs_RxGwwlC0
HGCAL Absorber Assembly Test in Taxila, Pakistan
YouTube video by CMS Experiment
youtu.be
January 23, 2026 at 1:49 PM
This is how the massive steel structure for the new CMS calorimeter, HGCAL, was tested! 👷
Last summer the structure that will house the delicate HGCAL cassettes was assembled in Pakistan and rotated to test its integrity.
📽️ Watch the timelapse: youtu.be/Xs_RxGwwlC0
Last summer the structure that will house the delicate HGCAL cassettes was assembled in Pakistan and rotated to test its integrity.
📽️ Watch the timelapse: youtu.be/Xs_RxGwwlC0
From decoding the human genome to exploring the universe, science has made huge strides in the 21st century. - www.nationalgeographic.com/science/arti...
The biggest scientific breakthroughs of the last 25 years—and a few to watch
From decoding the human genome to exploring the universe, science has made huge strides in the 21st century.
www.nationalgeographic.com
January 22, 2026 at 8:19 PM
From decoding the human genome to exploring the universe, science has made huge strides in the 21st century. - www.nationalgeographic.com/science/arti...
Proud supervisor! Great job by Gabriele 🤩🍝⚛️😎 who will become a doctor tomorrow!
www.instagram.com/reel/DT0dE0F...
www.instagram.com/reel/DT0dE0F...
January 22, 2026 at 5:13 PM
Proud supervisor! Great job by Gabriele 🤩🍝⚛️😎 who will become a doctor tomorrow!
www.instagram.com/reel/DT0dE0F...
www.instagram.com/reel/DT0dE0F...
Missing momentum is effectively the only way that the main detectors at the LHC (like CMS) can measure the indirect signs of neutrinos (or undiscovered particles). This #CMSPaper present how we use #machinelearning to make our missing momentum measurement much, much better: arxiv.org/abs/2509.12012
January 21, 2026 at 9:47 PM
Missing momentum is effectively the only way that the main detectors at the LHC (like CMS) can measure the indirect signs of neutrinos (or undiscovered particles). This #CMSPaper present how we use #machinelearning to make our missing momentum measurement much, much better: arxiv.org/abs/2509.12012
This #CMSPaper examines the missing energy from neutrino pairs in top quark pair production. Accurate measurement of those neutrinos is crucial for simulating top quarks in the standard model and for setting constraints on invisible particle production with top quarks. arxiv.org/abs/2510.00160
January 21, 2026 at 7:47 PM
This #CMSPaper examines the missing energy from neutrino pairs in top quark pair production. Accurate measurement of those neutrinos is crucial for simulating top quarks in the standard model and for setting constraints on invisible particle production with top quarks. arxiv.org/abs/2510.00160
As renaming geographic locations is a thing now I see an easy way to protect #Greenland. Just rename it to Epsteinland.
You’re welcome.
You’re welcome.
January 21, 2026 at 7:21 AM
As renaming geographic locations is a thing now I see an easy way to protect #Greenland. Just rename it to Epsteinland.
You’re welcome.
You’re welcome.
This #CMSPaper investigates different #AI #machinelearning methods that aim to find jets that are inconsistent with the standard model. It shows that a new method called #Wasserstein normalized autoencodes works much better than other neural networks arxiv.org/abs/2510.02168
January 20, 2026 at 9:05 PM
This #CMSPaper investigates different #AI #machinelearning methods that aim to find jets that are inconsistent with the standard model. It shows that a new method called #Wasserstein normalized autoencodes works much better than other neural networks arxiv.org/abs/2510.02168
If you got here because of nails 💅💅🏻💅🏼💅🏽💅🏾💅🏿, I totally understand!
But of course I also deal with particle physics as that’s my day job 🤓😇👷♀️⚛️
Check out this nice post on #darkmatter on Instagram, prepared by DESY intern Sofia www.instagram.com/p/DTu2TdMCOj... #wisskomm #scicomm
But of course I also deal with particle physics as that’s my day job 🤓😇👷♀️⚛️
Check out this nice post on #darkmatter on Instagram, prepared by DESY intern Sofia www.instagram.com/p/DTu2TdMCOj... #wisskomm #scicomm
January 20, 2026 at 8:05 PM
If you got here because of nails 💅💅🏻💅🏼💅🏽💅🏾💅🏿, I totally understand!
But of course I also deal with particle physics as that’s my day job 🤓😇👷♀️⚛️
Check out this nice post on #darkmatter on Instagram, prepared by DESY intern Sofia www.instagram.com/p/DTu2TdMCOj... #wisskomm #scicomm
But of course I also deal with particle physics as that’s my day job 🤓😇👷♀️⚛️
Check out this nice post on #darkmatter on Instagram, prepared by DESY intern Sofia www.instagram.com/p/DTu2TdMCOj... #wisskomm #scicomm
The LHC recently collided Oxygen and Neon ions. That is an important input to understanding how nuclear interactions change depending on the size of the colliding objects. This #CMSPaper observes "collective flow", essentially a sign of the quark gluon plasma, in those collisions buff.ly/NcLWdAj
January 19, 2026 at 6:47 PM
The LHC recently collided Oxygen and Neon ions. That is an important input to understanding how nuclear interactions change depending on the size of the colliding objects. This #CMSPaper observes "collective flow", essentially a sign of the quark gluon plasma, in those collisions buff.ly/NcLWdAj
I heard last week that the physics teacher of the daughter of one of my colleagues told the daughter that girls who do their nails don’t do physics. Sigh.
So, here are the nails of an internationally leading particle physics professor. My nails.
Don’t believe the gatekeepers! #womeninSTEM
So, here are the nails of an internationally leading particle physics professor. My nails.
Don’t believe the gatekeepers! #womeninSTEM
January 19, 2026 at 12:17 PM
I heard last week that the physics teacher of the daughter of one of my colleagues told the daughter that girls who do their nails don’t do physics. Sigh.
So, here are the nails of an internationally leading particle physics professor. My nails.
Don’t believe the gatekeepers! #womeninSTEM
So, here are the nails of an internationally leading particle physics professor. My nails.
Don’t believe the gatekeepers! #womeninSTEM
The production of top quark pairs together with a W boson is a great way to test the quality of standard model predictions. This #CMSPaper measures provides boundaries on things like the difference between ttW+/- production, a very sensitive quantity to test the predictions arxiv.org/abs/2509.13512
January 18, 2026 at 11:03 AM
The production of top quark pairs together with a W boson is a great way to test the quality of standard model predictions. This #CMSPaper measures provides boundaries on things like the difference between ttW+/- production, a very sensitive quantity to test the predictions arxiv.org/abs/2509.13512
You may have noticed that I stopped numbering the #CMSPapers I posted about. This is mostly because the numbering is kind of ambiguous. But we have published over 1400 papers (of which 1380+ on LHC data) since 2009 already!
check them all out (searchable) here: cms-results-search.web.cern.ch
check them all out (searchable) here: cms-results-search.web.cern.ch
January 18, 2026 at 9:03 AM
You may have noticed that I stopped numbering the #CMSPapers I posted about. This is mostly because the numbering is kind of ambiguous. But we have published over 1400 papers (of which 1380+ on LHC data) since 2009 already!
check them all out (searchable) here: cms-results-search.web.cern.ch
check them all out (searchable) here: cms-results-search.web.cern.ch
The production of the Higgs boson along with an undiscovered hypothetical particle is an important signature for detecting physics beyond the standard model. This #CMSPaper looks for the "Higgs boson+jet not consistent with the standard model" signature (we didn't see any): arxiv.org/abs/2509.13635
January 17, 2026 at 10:12 AM
The production of the Higgs boson along with an undiscovered hypothetical particle is an important signature for detecting physics beyond the standard model. This #CMSPaper looks for the "Higgs boson+jet not consistent with the standard model" signature (we didn't see any): arxiv.org/abs/2509.13635
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
January 17, 2026 at 9:12 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
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
January 16, 2026 at 9:42 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
Am Montag gehe ich ins Gymnasium in Heimfeld. Und ich komme mit Teilchenphysik-Goodies! #WirWollensWissen #wisskomm #swag
January 16, 2026 at 8:42 PM
Am Montag gehe ich ins Gymnasium in Heimfeld. Und ich komme mit Teilchenphysik-Goodies! #WirWollensWissen #wisskomm #swag
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
January 16, 2026 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
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
January 16, 2026 at 11:27 AM
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
cool nieuws item met de Vlaamse regering op CERN vrtnws.be/p.owAWNeAwLlY
"Iederéén zou moeten komen kijken", minister-president Diependaele onder de indruk van deeltjesversneller CERN in Genève | VRT NWS: nieuws
Altijd op de hoogte van het laatste nieuws uit binnen- en buitenland dankzij de betrouwbare en diepgaande berichtgeving van VRT NWS.
vrtnws.be
January 15, 2026 at 6:22 PM
cool nieuws item met de Vlaamse regering op CERN vrtnws.be/p.owAWNeAwLlY
Nice article about the (unexpected!) excess in the low mass top quark spectrum. A result with an important contribution from DESY btw :) physicsworld.com/a/cms-spots-...
CMS spots hints of a new form of top‑quark matter – Physics World
A threshold excess in top–antitop production hints at toponium‑like physics and supports non‑relativistic QCD models
physicsworld.com
January 15, 2026 at 1:03 PM
Nice article about the (unexpected!) excess in the low mass top quark spectrum. A result with an important contribution from DESY btw :) physicsworld.com/a/cms-spots-...
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
January 14, 2026 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
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:
January 14, 2026 at 1:03 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:
Delighted that we can provide a voice to let young people talk about science, lab life, science communication and so much more!
This is exactly the idea of this insta account, very excited to see the response
This is exactly the idea of this insta account, very excited to see the response
January 14, 2026 at 12:52 PM
Delighted that we can provide a voice to let young people talk about science, lab life, science communication and so much more!
This is exactly the idea of this insta account, very excited to see the response
This is exactly the idea of this insta account, very excited to see the response
Eine weitere schöne wissenschaftliche Kommunikation zur Teilchenphysik aus Österreich. Cooles Projekt! 🤩
sound.orf.at/radio/oe1/se...
sound.orf.at/radio/oe1/se...
ORF Sound
ORF Sound ist das digitale Audio-Angebot des ORF. Alle öffentlich-rechtlichen Radiosender Österreichs live und die besten Inhalte kuratiert, 30 Tage on Demand.
sound.orf.at
January 14, 2026 at 8:06 AM
Eine weitere schöne wissenschaftliche Kommunikation zur Teilchenphysik aus Österreich. Cooles Projekt! 🤩
sound.orf.at/radio/oe1/se...
sound.orf.at/radio/oe1/se...
This #CMSPaper reports a #nullresult in signatures, as particles that don't show up in the @cmsexperiment are produced alongside particles that we can see. Those particles could be linked to dark matter, or new Higgs particles, or even more exotic undiscovered particles arxiv.org/abs/2510.12396
January 13, 2026 at 1:03 PM
This #CMSPaper reports a #nullresult in signatures, as particles that don't show up in the @cmsexperiment are produced alongside particles that we can see. Those particles could be linked to dark matter, or new Higgs particles, or even more exotic undiscovered particles arxiv.org/abs/2510.12396