First high-precision measurement of the mass of the W boson at the LHC

February 12, 2018, CERN
Display of a candidate event for a W boson decaying into one muon and one neutrino from proton-proton collisions recorded by ATLAS with LHC stable beams at a collision energy of 7 TeV.  (Image: CERN

In a paper published today in the European Physical Journal C, the ATLAS Collaboration reports the first high-precision measurement at the Large Hadron Collider (LHC) of the mass of the W boson. This is one of two elementary particles that mediate the weak interaction – one of the forces that govern the behaviour of matter in our universe. The reported result gives a value of 80370±19 MeV for the W mass, which is consistent with the expectation from the Standard Model of Particle Physics, the theory that describes known particles and their interactions.

The measurement is based on around 14 million W bosons recorded in a single year (2011), when the LHC was running at the energy of 7 TeV. It matches previous measurements obtained at LEP, the ancestor of the LHC at CERN, and at the Tevatron, a former accelerator at Fermilab in the United States, whose data made it possible to continuously refine this measurement over the last 20 years.

The W boson is one of the heaviest known particles in the universe. Its discovery in 1983 crowned the success of CERN's Super proton-antiproton Synchrotron, leading to the Nobel Prize in physics in 1984. Although the properties of the W boson have been studied for more than 30 years, measuring its mass to high precision remains a major challenge.

"Achieving such a precise measurement despite the demanding conditions present in a hadron collider such as the LHC is a great challenge," said the physics coordinator of the ATLAS Collaboration, Tancredi Carli. "Reaching similar precision, as previously obtained at other colliders, with only one year of Run 1 data is remarkable. It is an extremely promising indication of our ability to improve our knowledge of the Standard Model and look for signs of new physics through highly accurate measurements."

The Standard Model is very powerful in predicting the behaviour and certain characteristics of the and makes it possible to deduce certain parameters from other well-known quantities. The masses of the W boson, the top quark and the Higgs boson for example, are linked by quantum physics relations. It is therefore very important to improve the precision of the W boson mass measurements to better understand the Higgs boson, refine the Standard Model and test its overall consistency.

Remarkably, the mass of the W boson can be predicted today with a precision exceeding that of direct measurements. This is why it is a key ingredient in the search for new , as any deviation of the measured mass from the prediction could reveal new phenomena conflicting with the Standard Model.

The measurement relies on a thorough calibration of the detector and of the theoretical modelling of the W boson production. These were achieved through the study of Z events and several other ancillary measurements. The complexity of the analysis meant it took almost five years for the ATLAS team to achieve this new result. Further analysis with the huge sample of now-available LHC data, will allow even greater accuracy in the near future.

Explore further: ATLAS releases first measurement of W mass using LHC data

More information: undefined undefined et al. Measurement of the W-boson mass in pp collisions at $$sqrt{s}=7, hbox {TeV}$$s=7TeV with the ATLAS detector, The European Physical Journal C (2018). DOI: 10.1140/epjc/s10052-017-5475-4

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Hyperfuzzy
1.5 / 5 (8) Feb 12, 2018
There are no such things as particles! Only the diametrical spherical fields, the center identified as charge. They are immortal. They do not occupy space. The fields only affect other centers. That's it! No GR, No Standard Model, No Big Bang, No Strings. Just these, charge, no beginning no end. The reality of Space vs the Conceptual!
Hyperfuzzy
1 / 5 (6) Feb 12, 2018
Come on guys, this game was over before it started!
jd_
5 / 5 (7) Feb 12, 2018
And the kooks weigh in.
rrwillsj
5 / 5 (7) Feb 12, 2018
Oh jd! The kooks can't 'weigh' in. They are denying the reality of gravity and quantum improbability. They are like balloons puffed up at a child's b-day party and then released to "spurttzzz" away, all over the internet.
Hyperfuzzy
1 / 5 (5) Feb 12, 2018
Oh jd! The kooks can't 'weigh' in. They are denying the reality of gravity and quantum improbability. They are like balloons puffed up at a child's b-day party and then released to "spurttzzz" away, all over the internet.

And here we are! A room without science talking and disrespecting reality, unscientifically!
Captain Stumpy
4.4 / 5 (7) Feb 12, 2018
@hyper
And here we are! A room without science talking and disrespecting reality, unscientifically!
and your post here contained science?
They are immortal. They do not occupy space. The fields only affect other centers. That's it! No GR, No Standard Model, No Big Bang... Just these, charge, no beginning no end. The reality of Space vs the Conceptual!
there is no sound evidentiary basis for your claims about no beginning/end - so that is considered opinion

there is ample evidentiary support directly refuting your argument of no GR, no big bang and no standard model, so that makes your claim not only blatantly false, but also pseudoscience

therefore your own comment is "A room without science talking and disrespecting reality, unscientifically!"
PowerMax
4 / 5 (4) Feb 13, 2018
i can't understand if Hyperfuzzy is trolling or genuinely stupid
Anda
4 / 5 (4) Feb 13, 2018
My bet is genuinely stupid
Captain Stumpy
5 / 5 (4) Feb 13, 2018
@PowerMax
i can't understand if Hyperfuzzy is trolling or genuinely stupid
Hyper is not stupid as he's displayed functional intellect in certain areas that indicate a basic grasp of physics and basic sciences

he is just dedicated to his personal untested, unverified beliefs to the point of exclusion of factual data that refutes him

Turgent
3 / 5 (2) Feb 13, 2018
This is a large paper. With very little exception there is no calculus used. It consists of algebra and statistics. Have any kooks read this paper or have a comment of any insight or critique?

Can any kook figure out how much energy a particle = 80370 ± 19 MeV is?
Zzzzzzzz
5 / 5 (4) Feb 13, 2018
@PowerMax
i can't understand if Hyperfuzzy is trolling or genuinely stupid
Hyper is not stupid as he's displayed functional intellect in certain areas that indicate a basic grasp of physics and basic sciences

he is just dedicated to his personal untested, unverified beliefs to the point of exclusion of factual data that refutes him



Concluding that the most likely state is delusion? There is a case to be made that excessive delusion can be caused by stupidity.....
PowerMax
5 / 5 (2) Feb 13, 2018
@PowerMax
i can't understand if Hyperfuzzy is trolling or genuinely stupid
Hyper is not stupid as he's displayed functional intellect in certain areas that indicate a basic grasp of physics and basic sciences

he is just dedicated to his personal untested, unverified beliefs to the point of exclusion of factual data that refutes him


ignoring OVERWHELMING evidence (and tons of theoretical work) in favor of claims based only on personal "philosophical" arguments is certainly not being smart. But hey, what do I know. Maybe he is the next A. Einstein.
mackita
not rated yet Feb 13, 2018
Can any kook figure out how much energy a particle = 80370 ± 19 MeV is?
It's 3.078 E-12 calorie (nutritional). One calorie (1mWh) is required for heating one milliliter of water by one degree of Centigrade. The smallest droplet of water visible in fog has a diameter 20 microns and volume 10E-11 ml, so that the decay of 1000 W bosons could heat it to boiling point. But W boson only rarely decays to pure photons only.
Hyperfuzzy
1 / 5 (2) Feb 13, 2018
Captain, we seem to have lost our way!
mackita
not rated yet Feb 13, 2018
Have any kooks read this paper or have a comment of any insight or critique?
No prob... For example the nonzero mass of W boson implies, that another bosons should also have their rest mass, including photons. This is because the gauge theory requires, that only bosons of zero rest mass can exchange forces at infinite distance - and the distance range of gluon forces are 10E-15 meters. The gluon bosons are considered massless in Standard Model, because they're outweighted by already very dense environment of atom nuclei - so that outside of them they would have rest mass about 140 MeV. The similar factor should be therefore added also to W/Z bosons masses: it's exactly measured but incorrect value IMO.
Captain Stumpy
5 / 5 (2) Feb 13, 2018
@hyper
Captain, we seem to have lost our way!
... and that is why you should always, *always*, listen to your NCO's when you're a butterbar (or 1Lt)

.

.

I ain't lost

Turgent
not rated yet Feb 13, 2018
Can any kook figure out how much energy a particle = 80370 ± 19 MeV is?
It's 3.078 E-12 calorie (nutritional). One calorie (1mWh) is required for heating one milliliter of water by one degree of Centigrade. The smallest droplet of water visible in fog has a diameter 20 microns and volume 10E-11 ml, so that the decay of 1000 W bosons could heat it to boiling point. But W boson only rarely decays to pure photons only.


Nice to see the discussion of science.
Turgent
not rated yet Feb 13, 2018


Have any kooks read this paper or have a comment of any insight or critique?

No prob... For example the nonzero mass of W boson implies, that another bosons should also have their rest mass, including photons. This is because the gauge theory requires, that only bosons of zero rest mass can exchange forces at infinite distance - and the distance range of gluon forces are 10E-15 meters. The gluon bosons are considered massless in Standard Model, because they're outweighted by already very dense environment of atom nuclei - so that outside of them they would have rest mass about 140 MeV. The similar factor should be therefore added also to W/Z bosons masses: it's exactly measured but incorrect value IMO.


I have to say you are beyond me here.
Hyperfuzzy
1 / 5 (3) Feb 13, 2018


Have any kooks read this paper or have a comment of any insight or critique?

No prob... For example the nonzero mass of W boson implies, that another bosons should also have their rest mass, including photons. This is because the gauge theory requires, that only bosons of zero rest mass can exchange forces at infinite distance - and the distance range of gluon forces are 10E-15 meters. The gluon bosons are considered massless in Standard Model, because they're outweighted by already very dense environment of atom nuclei - so that outside of them they would have rest mass about 140 MeV. The similar factor should be therefore added also to W/Z bosons masses: it's exactly measured but incorrect value IMO.


I have to say you are beyond me here.

Mass is undefined! The field is created by bipolar fields, and the centers are called charge. So first define all objects! There's nothing in the center, That's an unresolved paradigm!
Hyperfuzzy
1 / 5 (2) Feb 14, 2018
This is far too much fun, completely false theory, theoretically, logically, mathematically, and completely without merit! Therefore we are living in a sea of nonsense!

There is no beginning and no end! Only these infinite spherical fields, we detect as charge! Or is it a material with these tiny knots?

Anyway, charge seems to work for my reality!https://drive.goo...nXPRU3FG
Hyperfuzzy
1 / 5 (1) Feb 14, 2018
Particles don't exist and have never been defined! Charge can not be subdivided physically, it represents a point within a unique, to us, field! I use the term unique as in superposition applies in order to build matter! The field and charge motion is described by Maxwell. Elements are defined with an NxN set of equations describing the contents, remove a charge to define ions, easier to build the steady state then the orbiters; therefore, everything is a set of equations described with 2 known entities. The steady state, the dynamic ... note: The fields exist from its center to infinity, fields don't affect fields, only field centers.
PowerMax
not rated yet Feb 15, 2018
This is far too much fun, completely false theory, theoretically, logically, mathematically, and completely without merit! Therefore we are living in a sea of nonsense!

There is no beginning and no end! Only these infinite spherical fields, we detect as charge! Or is it a material with these tiny knots?

Anyway, charge seems to work for my reality!https://drive.goo...nXPRU3FG

HAHAHAHAHAHAH!!!! what is that """""""""""""article"""""""""""""""""""??!! oh man! :'''D
Hyperfuzzy
not rated yet Feb 15, 2018
This is far too much fun, completely false theory, theoretically, logically, mathematically, and completely without merit! Therefore we are living in a sea of nonsense!

There is no beginning and no end! Only these infinite spherical fields, we detect as charge! Or is it a material with these tiny knots?

Anyway, charge seems to work for my reality!https://drive.goo...nXPRU3FG

HAHAHAHAHAHAH!!!! what is that """""""""""""article"""""""""""""""""""??!! oh man! :'''D

did u read it all! Blow your mind? That's Logic!
Hyperfuzzy
not rated yet Feb 15, 2018
Mass is so 17th century; better knowing it as 2N centers, bipolar. Thus someone took "nothing" and split it into bipolar fields, that add to 0 if at the same point, or 2*infinity = reality!
Hyperfuzzy
not rated yet Feb 15, 2018
Mass is so 17th century; better knowing it as 2N centers, bipolar. Thus someone took "nothing" and split it into bipolar fields, that add to 0 if at the same point, or 2*infinity = reality!

Integer set; therefore countable, and the same count at any point at any time. The Continuum!
TechnoCreed
5 / 5 (1) Feb 15, 2018
This is a large paper. With very little exception there is no calculus used. It consists of algebra and statistics. Have any kooks read this paper or have a comment of any insight or critique?

Can any kook figure out how much energy a particle = 80370 ± 19 MeV is?

Since kook is pretty much a pejorative term, no sensible person would reply to your post. You could have at least used geek since it has pretty much lost its pejorative connotation. But the preferred term is science aficionado.
TechnoCreed
5 / 5 (3) Feb 15, 2018
Can any kook figure out how much energy a particle = 80370 ± 19 MeV is?
It's 3.078 E-12 calorie (nutritional). One calorie (1mWh) is required for heating one milliliter of water by one degree of Centigrade. The smallest droplet of water visible in fog has a diameter 20 microns and volume 10E-11 ml, so that the decay of 1000 W bosons could heat it to boiling point. But W boson only rarely decays to pure photons only.


Nice to see the discussion of science.

You asked a kook to reply, so a kook replied. I had to unmask the comment to make sure because Hyperfuzzy and mackita are ignored. It is mackita; what you should know about him is that he is better known as Zephir or the Zephir troll. He is present in pretty much all the science blogs there is, but no one cares about him anymore. He is a self taught person from Czech Republic who promote alternative physics, so the answer you are going to get from him is pretty much bullshit.
TechnoCreed
not rated yet Feb 15, 2018
Can any kook figure out how much energy a particle = 80370 ± 19 MeV is?
It's 3.078 E-12 calorie (nutritional). One calorie (1mWh) is required for heating one milliliter of water by one degree of Centigrade. The smallest droplet of water visible in fog has a diameter 20 microns and volume 10E-11 ml, so that the decay of 1000 W bosons could heat it to boiling point. But W boson only rarely decays to pure photons only.


Nice to see the discussion of science.

Let's analyze mackita's replies.

1.
It's 3.078 E-12 calorie (nutritional)
Alright his conversion is good https://www.wolfr...+to+Kcal But nutritional the Calorie written with a capital "C" is not an adequate unit to use in physics... it should have been in Joule but the use of kcal would have prevented any confusion.

tbc
TechnoCreed
not rated yet Feb 15, 2018
...

2.
One calorie (1mWh) is required for heating one milliliter of water by one degree of Centigrade.
There we go ! confusion between Calorie and calorie wich is a unit a 1000 times smaller, see here: https://en.wikipe.../Calorie

3.
The smallest droplet of water visible in fog has a diameter 20 microns and volume 10E-11 ml
Close but no cigar he is off by 3 orders of magnitude. 10e-11 liter not milliliter. The correct answer is 3.35 x 10e-11 liter, see here: https://www.wolfr...id+water

tbc
Hyperfuzzy
not rated yet Feb 15, 2018
...

2.
One calorie (1mWh) is required for heating one milliliter of water by one degree of Centigrade.
There we go ! confusion between Calorie and calorie wich is a unit a 1000 times smaller, see here: https://en.wikipe.../Calorie

tbc

So h nu is what? It's made up! It's a best fit. Obviously translated to a perspective, instead of probability! But, there is motion of the field and motion of the field centers. With clarity, this is all there is.
Turgent
5 / 5 (1) Feb 15, 2018
Cool using WolframAlpha, in this forum. Now that is genius.
TechnoCreed
not rated yet Feb 15, 2018
N.B.: The term centigrade is obsolete. He should have wrote Celcius.
TechnoCreed
not rated yet Feb 15, 2018
...

4.
...so that the decay of 1000 W bosons could heat it to boiling point.
Wow his quantity was off by 3 orders of magnitude but his final answer is somewhat ok!!! With this convoluted artistry he should try figure skating he would get high marks. By the way the answer should have been 10 W bosons is the equivalent energy needed to raise 3.35 x 10e-11 liter of water by 1°C, 1000 W bosons to boiling point if your water is at 0°C to start with.

5.
But W boson only rarely decays to pure photons only.
Wrong ! It never decays to pure photons... It is a weak force carrier so it does not have any electromagnetic signature, see the W decay mode here: http://pdg.lbl.go...oson.pdf

tbc
TechnoCreed
not rated yet Feb 15, 2018
...



Have any kooks read this paper or have a comment of any insight or critique?

No prob... For example the nonzero mass of W boson implies, that another bosons should also have their rest mass, including photons. This is because the gauge theory requires, that only bosons of zero rest mass can exchange forces at infinite distance - and the distance range of gluon forces are 10E-15 meters. The gluon bosons are considered massless in Standard Model, because they're outweighted by already very dense environment of atom nuclei - so that outside of them they would have rest mass about 140 MeV. The similar factor should be therefore added also to W/Z bosons masses: it's exactly measured but incorrect value IMO.


I have to say you are beyond me here.

Now let's analyse the second part of his reply.

tbc
mackita
not rated yet Feb 15, 2018
W-boson never decays to pure photons
The W bosons are produced by quark anti-quark annihilation, which could lead to diphoton decay - at least in principle.. But due to quark confinement we can't observe this through the normal scattering experiments we use to observe such phenomena. However, quarks annihilating into two photons can be observed in processes such as neutral pion decay. The πo is composed of either a down and anti-down quark or a up and anti-up quark. It has been observed that the πo decays into two photons via weak force boson - which would means the quark and anti-quark that composed it annihilated!
the answer you are going to get from him is pretty much bullshit...blah blah...Wow his quantity was off by 3 orders of magnitude but his final answer is somewhat ok!!
The secret of geniality is in hiding its sources...;-)
Hyperfuzzy
not rated yet Feb 15, 2018
...;-)

All that exist is a set of fields. You could say a cow jumped over the moon; then, the impulse response from its takeoff inspired the measure! It's only the fields!
TechnoCreed
not rated yet Feb 15, 2018
...

6.
No prob... For example the nonzero mass of W boson implies, that another bosons should also have their rest mass, including photons. This is because the gauge theory requires, that only bosons of zero rest mass can exchange forces at infinite distance - and the distance range of gluon forces are 10E-15 meters.
A word salad... all bosons are weightless within their interaction range. Wand Z bosons that are detected outside their range have mass because they interact with the Higgs field. http://hyperphysi...for.html Bosons interactions are very exceptional so you can consider that there are no interaction between bosons just between bosons and fermions.

tbc
TechnoCreed
not rated yet Feb 15, 2018
...

7.
The gluon bosons are considered massless in Standard Model, because they're outweighted by already very dense environment of atom nuclei - so that outside of them they would have rest mass about 140 MeV.
Talking about gluons mass is moot because they are constrained within their hadron bag (range of interaction).

8.
The similar factor should be therefore added also to W/Z bosons masses: it's exactly measured but incorrect value IMO.
This is total bullshit but Zephir always build a pretext to discredit science.

Reading Zephir's comment is without interest that is why he is ignored. Unlike some other obnoxious posters, his comments are polite so I can handle seeing them.
milnik
not rated yet 23 hours ago
There are two major misconceptions in investigating the occurrence of particle collisions.
The first and fundamental error of science is the use of Einstein's formula for converting the mass into energy: E = m.č ^ 2, and from here it is: m = E / č ^ 2, This formula has nothing to do with natural laws, nor energy, from the mass, through the speed of light, can logically be used.
Another mistake and misconception of science is that it does not know anything about the empty space (particles of the particle conduit) being filled, and how this substance behaves in an empty space when the magnetic field strength and particle velocity increases, which is aimed at "suicide ". Science does not realize that within Aether, from which matter forms, and that AETHER changes the behavior of matter, if magnetism changes. That's why these bosons and all other particles are obtained in collisions, just "dead-born Frankenstein of form and behavior".
mackita
not rated yet 18 hours ago
Zephir always build a pretext to discredit science
Karl Popper: The only way how to do the real science is to attempt for its falsification.

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