Visit CERN sites new to Google Street View


Link to view:,6.056625,3a,75y,288.51h,94.5t/data=!3m6!1e1!3m4!1sNy0OR587lg2ogm2JXscnog!2e0!7i13312!8i6656,6.047789,3a,75y,23.27h,93.73t/data=!3m7!1e1!3m5!1seWymMV0gcOAtt8IyRcqU6Q!2e0!3e5!7i13312!8i6656?hl=en-US

Link to view:,6.047789,3a,75y,23.27h,93.73t/data=!3m7!1e1!3m5!1seWymMV0gcOAtt8IyRcqU6Q!2e0!3e5!7i13312!8i6656?hl=en-US

Reddit CERN AMA (Ask Me Anything) Round up

Below are a few of the questions asked and responses given by a team of CERN scientists doing a AskMeAnything post on

Hi reddit!

Last week, the Large Hadron Collider had its first-ever collisions at a centre-of-mass energy of 13 teraelectronvolts (TeV), breaking the world record for the highest energy attained in a particle accelerator. We’re very excited to be back after our previous AMAs [1, 2], to discuss what lies ahead. We are:

  • Reyes Alemany Fernandez (raf), LHC operations
  • Andreas Weiler (aw), DESY and CERN Theory division
  • Federico Ronchetti (fr), INFN Frascati and ALICE Experiment
  • Beate Heinemann (bh), Lawrence Berkeley National Lab and ATLAS Experiment
  • Luca Malgeri (lm), CERN and CMS Experiment
  • Adam Morris (am), University of Edinburgh and LHCb Experiment

We’ll sign our responses with our initials so you know who said what. Just to be clear, we are speaking with you in our personal capacities and CERN does not necessarily support the views expressed during the AMA. Joining us are a few of our friends from CERN:

We’ll answer your questions from 16:00 until 17:30 CEST (UTC+02).

About CERN and the LHC

CERN is the European Laboratory for Particle Physics, located in Geneva, Switzerland. Its flagship accelerator is the Large Hadron Collider (LHC), which has four main particle detectors: ALICE, ATLAS, CMS and LHCb. Nearly three years ago, CMS and ATLAS announced the discovery of a new particle that we now know is a Higgs boson. Scientists here are now looking forward to physics research at unprecedented energies.

Get social!

For updates, news and more, head over to our unofficial home on reddit: /r/CERN!

Are there any specific theories/models you’ll be able to confirm or rule out?

CERN team response:

In general: not directly. Our detector can make very precise measurements that give sensitivity to possible new heavy particles at energy scales far below their masses. If we measure something that disagrees with its Standard Model prediction, then that suggests there is something new, but it’s difficult to conclusively say which model might be responsible.

 I know from that song that “LHCb sees where the antimatter’s gone.” Will collisions at 13 TeV give you new data to understand the baryon asymmetry in a way that lower energy collisions couldn’t? How?

CERN team response:

During the next few years (“Run 2”), LHCb expects to more than double the amount of proton-proton collisions collected in 2011 and 2012 (technical talk: we hope to add 5 fb−1 of collisions to our existing 3 fb−1). In addition, the production rates for B hadrons are expected to roughly double with the increase in energy.

The size of the uncertainties on a lot of key measurements relating to matter-antimatter asymmetry are expected to decrease significantly.

See slide 19 in this presentation, and compare the columns highlighted in brown and blue. (am)

Explain to me like I am five: why are you doing this and what makes it important? What could we/you do with this data in the future?

CERN team response:

I can give you an example. In 1800 the study of electricity and magnetism were considered an highly theoretical study with no practical uses. At most was used for circus shows. Once understood by means of theory and experiments it shaped the modern world. Try to think how could you live without electricity? The research we are carrying out at cern may seem far from everyday life today however will bring forward our knowledge of the natural phenomena and it has already practical spin offs. For instance accelerator technology is used for inoperable cancer surgery and as you may know the software protocol that powers the web was invented at cern.

Another CERN response:

Human beings do certain things to survive: eat, drink, make babies, and learn about the world around us. We are naturally curious animals. Over time, we have found that, every time we learn something new about nature, the information is used by our children or their children to help them survive. This is not just important; it is essential. We are not as fast or as strong as many other animals. But, we do have this bump on our shoulders that helps us to keep from getting eaten or from dying of disease. We have learned how to farm, how to make electricity, how to travel and communicate around the world. All of these started with basic research. Your parent’s mobile phone (I know you are 5 and might not have one yet) can do things it would not be able to do without the contributions of Faraday, Einstein, Niels Bohr, and many others. In addition, our pursuit of these discoveries often leads to more direct applications. Examples are MRIs, PET scans, touch screens, and the Worldwide Web. We do not know exactly what our discoveries and measurements will lead to. It is too soon to say. But, we do know they will contribute significantly to our understanding of our world. And, as human being, we have no choice but to pursue them. It is a question of survival.

We’re looking for all kinds of crazy things at the LHC. As experimentalists, which predictions by theorists does everybody like best? Are you hoping for SuperSymmetry? Extra dimensions? Dark matter candidate? Which triggers do you have your eye on?

CERN team response:

Indeed we are looking for a very broad range of things at the LHC, and Supersymmetry, Dark matter and extra dimensions are among them. As an experimental physicist I don’t actually care myself which of them (if ANY) is right as I just want to find out about what Nature is. We conduct typically 100 searches for particles at any moment in time, and have also several hundred triggers which decide which data we record. Dark matter is indeed a particularly well motivated thing to look for as we know for sure it exists! We just don’t know what it is and indeed we search for events with a large imbalance in momentum to find dark matter.


…What is the biggest thing limiting your research with the LHC?

CERN team response:

Currently the LHC is the most powerful machine in the world for this kind of research and it is ready to produce physics results at least for the next 20 years. In collider physics there are usually two limiting factors: 1) the total available energy (we are now at 13 TeV) and 2) the rate of collisions we produce. More energy opens up the possibility to produce more massive particles while the collisions rate increase the possibility of producing very rare processes. We are already addressing the collision rate with upgrades foreseen in the next few years that will push it up by two orders of magnitude. For a substantial increase in energy we have started studies for a new potential accelerator that might push it up by a factor of 10 but this will take several decades to be realized. We are sure that the LHC will show us the way to go before building the next machine!

As far as I understand dark matter doesn’t interact in any other way than gravity. Considering that any dark matter created in collisions will be much to small for the gravity to be detected. How will you study it? Will you just be looking at energy calculations and saying that some of the energy disappeared so it must be dark matter?

CERN team response:

Good question! Although we have very good evidence for dark matter interacting gravitationally, we don’t know if dark matter interacts with known matter. In order to produce dark matter at the LHC we need to assume that there is such a (possibly weak) interaction. In the most interesting models of physics beyond the Standard Model, dark matter does indeed interact with known matter: we can hope for man-made dark matter to be produced during the next run! Once produced we could then detect it using missing energy signatures. (Dark matter is also searched for in important underground and in satellite experiments.)

As a layman I’d like to ask, how powerful are typical collisions and how powerful is 13 TeV? How can the equipment be improved so higher energy collisions can be done?

CERN team response:

Clap your hands together. Congratulations, you’ve made a collision with more energy than the LHC : )

The difference though, is in the energy density. Stick a thumbtack against one of your palms, and clap again. Notice the difference? : D By concentrating the collision point, even with the same total energy we get a more intense collision. Protons are really, really, really tiny, so when they collide the energy density is huge, making the results a lot more interesting than a hand clap.

 Hi, so now that Higgs is around 125GeV are the theories of Multiverse hold any merit?

CERN team response:

Well… Before the discovery, we had two main contenders for physics beyond the standard model both predicting a range of Higgs masses (supersymmetry and the Higgs as a composite particle, like the e.g. the proton). Supersymmetry prefers a slightly lighter Higgs and composite Higgs models generically predict heavier Higgs particles. Both theories are still alive since the predicted Higgs ranges overlap with what has been discovered, but the allowed parameter spaces have been reduced and the kind of cancellations required to make it work have increased a bit.

Multiverse theories do not provide clear predictions for the Higgs mass, but they offer an explanation for the absence of any visible beyond the Standard Model physics (like new particles). Maybe one could say: as long as we keep not finding any evidence for physics beyond the Standard Model, theories of the multiverse will increase in attractiveness for some physicists.

When will the next update meeting be about the newer particles that you found this time around with the higher energy collisions? Do you expect to see newer particles this time around?

CERN team response:

The short answer is that we don’t know since we just don’t know what particles exist in Nature. We are exploring higher mass particles in the new run and if there are any we might find them in a few months, or it could take years or even decades. It depends a lot on what exactly the new particles are, what their mass is etc.


Hi, I always wondered if what you guy’s are doing could be done on a much smaller scale?

CERN team response:

It depends on what you mean by scale. If it is with “reduced energy”, this is, I’m afraid, not really possible. Energy gives us the way to explore new territories. The usual analogy is the microscope. The more energy we manage to put in the collisions, the more is the magnifying factor we can reach. If size is intended to be physical dimensions of the accelerator there are promising R&D studies on new technologies that would allow to reach the same energy in much smaller space and building up the equivalent of the LHC in a “room”. For more details you can have a look at this webpage.

Another CERN response:

Think of the LHC and its detectors as a lenses. The smaller the details you want to study the larger have to be the lenses. So the answer is no. The discovery potential of the LHC and its detectors cannot be achieved with smaller scales.


What is the biggest enigma in particle physics that you guys want to find answers in your lifetime?

CERN team response:

These are my top three questions:

  • What is dark matter is made of ? We know it’s there but have never been able to produce or detect it on earth.
  • Why the Higgs is so much lighter than the Planck mass? This is the so-called hierarchy problem ( Supersymmetry or a composite Higgs would explain this but we haven’t seen any evidence for either theory.
  • Why are there 3 copies of quarks and leptons? They have the same properties (e.g. charges and spins) but they have very different masses, e.g. the up quark is ~100,000x heavier than the top quark. We have no idea why that is.

Is there any possibility at all of you guys creating a black hole in the middle of Switzerland and wiping out the human race..?

Inital CERN team response:

In very simple terms, there is absolutely no risk of creating macroscopic black holes that are of any danger. For more details you can check a dedicated webpage where all details are given with also explanation about what we call hypothetical micro blackholes.

Follow up response by another in the CERN team to: You will never get rid of this question, right?

All of our reactions, every time”tumblr_inline_mjpodriFli1r79k32






I think I’ll end on that 😀

NASA | SDO: Year 5

Video description:

February 11, 2015 marks five years in space for NASA’s Solar Dynamics Observatory, which provides incredibly detailed images of the whole sun 24 hours a day. Capturing an image more than once per second, SDO has provided an unprecedentedly clear picture of how massive explosions on the sun grow and erupt ever since its launch on Feb. 11, 2010. The imagery is also captivating, allowing one to watch the constant ballet of solar material through the sun’s atmosphere, the corona.

In honor of SDO’s fifth anniversary, NASA has released a video showcasing highlights from the last five years of sun watching. Watch the movie to see giant clouds of solar material hurled out into space, the dance of giant loops hovering in the corona, and huge sunspots growing and shrinking on the sun’s surface.

The imagery is an example of the kind of data that SDO provides to scientists. By watching the sun in different wavelengths – and therefore different temperatures – scientists can watch how material courses through the corona, which holds clues to what causes eruptions on the sun, what heats the sun’s atmosphere up to 1,000 times hotter than its surface, and why the sun’s magnetic fields are constantly on the move.

Five years into its mission, SDO continues to send back tantalizing imagery to incite scientists’ curiosity. For example, in late 2014, SDO captured imagery of the largest sun spots seen since 1995 as well as a torrent of intense solar flares. Solar flares are bursts of light, energy and X-rays. They can occur by themselves or can be accompanied by what’s called a coronal mass ejection, or CME, in which a giant cloud of solar material erupts off the sun, achieves escape velocity and heads off into space. In this case, the sun produced only flares and no CMEs, which, while not unheard of, is somewhat unusual for flares of that size. Scientists are looking at that data now to see if they can determine what circumstances might have led to flares eruptions alone.

Goddard built, operates and manages the SDO spacecraft for NASA’s Science Mission Directorate in Washington, D.C. SDO is the first mission of NASA’s Living with a Star Program. The program’s goal is to develop the scientific understanding necessary to address those aspects of the sun-Earth system that directly affect our lives and society.