BARONS CYBER SKULL posted:

interstellar: 3 hours about using the power of love to escape a black hole and transmit the secret of space-time via morse code on a watch from a sarcastic robot

Swolegoat posted:

*x-files theme music starts playing

Displeased Moo Cow posted:

I was at a snooty wedding at a vineyard about a month ago. it was picturesque with a view of the ocean and vineyards and a stable. some rich prick eyed me up and down then muttered something to his mate, then called out "I'll pay you $200 to ride that horse over there bareback for 5 minutes" then smirked with his friends.

I leaped on that sucker bareback and sat on that beast right through the ceremony. people asked me what I was doing up there and I just said that rear end in a top hat over there bet me $300 to sit on a horse for 3 minutes. it was a good day to be me. my wife was embarrassed for some reason. I only got like $20 though. i didn't really want to draw ALL the attention away from the bride and groom and loudly demand full payment after all.

cheese-cube posted:

im late to LHC chat but this is the most kickass site: http://op-webtools.web.cern.ch/op-webtools/vistar/vistars.php (not at the moment though because they're not running). you can switch between diff readouts and poo poo via the top-left menu. "LHC Dashboard" is a good view when they're actually firing and whatnot. also "LHC Coordination" to see what they're actually doing. i used to just open heaps of windows and tile them to watch all the awesome poo poo that i only understood 10% of.

StarkingBarfish posted:

If you want to know more about it I can break it down for you.

Soldier of Fortran posted:

yes!

cheese-cube posted:

e: like on the "LHC Cryogenics" screen what do all those squares mean? i remember back when they were actually running poo poo they had to do a beam-dump because cryo failed i think and all of the sections were showing red.

StarkingBarfish posted:

Ok, so vistars started out as a kind of 'ceefax' or teletext thing back when the SPS was first running. It used to be played continuously on tvs around the cern site. Later, more screens were added for different accelerators on different tv channels, then the web came along and the interface went online while still looking p. much the same. I'll start with the SPS as it's running now so you can see more information there:



This is the SPS 'page 1', same as the LHC page 1 but for the accelerator just before the LHC. The SPS is the workhorse of CERN, it provides protons and lead ions for the LHC and doezens of other expleriments around CERN. At the moment it is running an ion supercycle. The supercycle is a daisy chain of inject-accelerate-extract of different energies and bunch intensities and it is represented by the two graphs you see there. In blue is the bunch current (how many particles are being accelerated) and in white is the beam energy. You can see at the start both are zero, then some ions get injected all at once from the PS so the blue plot jumps up a bit. After a while the white plot rises as the ions are accelerated up to high energy, then the blue plot drops down to zero as the accelerated ions are extracted and sent down a beamline to one of the experiments. Soon after the magnets ramp down. Then, 4 bunches of ions are injected, making the stairs shape you see. At the top of the stairs is a white bar- that's the timesweep telling you where the machine is now in the cycle. Some funky stuff happens at the top and one bunch is lost somehow- it might be being extracted at low energy as a pilot beam, or a specific expt. needs a lower energy beam for some reason. Then there's a slight acceleration, and the beam is slowly fed out at much lower current.

Below the plot you can see who is getting what: This beam is being sent to 4 targets for fixed target experiments. These are NA61, NA62, COMPASS and a few 'H' designations that I'm not sure of. 'NA' means North Area, which is where the beamlines are. Experiments that don't have their own name get a numeric identifier in the north area hall. You can find out what compass, NA61 and NA62 are here:

http://shine.web.cern.ch/
http://na62.web.cern.ch/NA62/Home/NA62Detector.html
http://wwwcompass.cern.ch/

Each will have different beam energy, intensity and target requirements. When the LHC is running, the supercycle is much longer to include protons for the LHC. For that they use maximum bunch current and energy, and even then it takes several cycles to fill the LHC before it accelerates further.



This is the page 1 for LHC. When LHC is running the same plot of beam intensity and energy is shown but for the LHC there isn't a supercycle as LHC doesn't send stuff to other accelerators/targets. All LHC does is fill-accelerate-collide the bunches it receives from the SPS.

On the lower right you have the beam interlock system which has various flags to tell whether beam can be injected and whether the experiments can take data or now.
- Link status of beam permits means 'if stuff is allowed in beam 1, is it also allowed in beam 2'.
- The global beam permit means 'are all safety interlocks closed: ie, are we allowed to have beam in the machine',
- Setup beam I'm less sure of, but I think it means can the state machine at the LHC side do everything up to but not including injection.
- Beam presence means is there any beam currently circling the accelerator (I know, duh, right? but if the current is very low sometimes it's hard to tell from the graph).
- Movable devices: there's one serious movable device in the form of LHCb's vertex detector, that sits on motorized rails and physically surrounds the beam during data taking. That needs permission to move in because if the beam isn't orbiting cleanly it can have a nice hole burnt into it, so the machine needs to grant permission to close around it.
- Stable beam: This is the last step in the LHC at startup- when the beams are brought together to collide and the beam orbits are stable this tells the experiments they can start taking physics data.

On the lower left is the AFS or 'active filling scheme' . This is decoded as 150nanoseconds between bunches, 104 bunches per beam of which 93 will collide in ATLAS and CMS, 8 will collide in ALICE and 93 in LHCb. The '8bpi' I *think* means 8 pilot bunches injected but this is less clear.



The cryogenics page lists the different sectors of the LHC and whether they're at the right temperature. Green means good to go, 1.8 kelvin. Red means the cryo lock has been lost and you can't put beam in the machine. They've only finished cooling down the magnets after the shutdown, and superconducting magnets are a pain- they need trained to operate stably, so they get cooled down, quench, are cooled again, quench, etc etc until they stop quenching. You can see on the graph on the lower left a few quenches where the temp. shoots up a bit and then they cool back down slowly. The LHC is divided into 8 sectors by 8 access points, so the sector between points 8 and 1 is S81.

The specific naming conventions I know less about, but you can see that one sector has tripped and lost the cryo permit. When running the LHC would dump the beam and wouldn't be able to inject until that went green again. Below you have also the superconducting RF cavity cryo status, and the 60A power lines too.

Valtaherra posted:

https://www.youtube.com/watch?v=y7YR9oVku4Q

wayfinder posted:

https://pbs.twimg.com/tweet_video/B_wYHGvU0AAAwRS.mp4

StarkingBarfish posted:

When any of the several thousand redundant safety interlocks and sensors around the ring trips, the beam is kicked out onto the dump. Even then it would burn a nice hole through the core if nothing else was done: It has to be defocussed first and is drawn across the face of the core in an 'e' shape to dissipate the heat evenly. This is what it looks like as it gets to the dump:

BooLoo posted:

this is from pages ago but holy poo poo!!!! I had this book when I was a kid

BooLoo posted:

you pulled a tab and all those green strips in the monitor moved so it looked like words were being typed. I can't remember what it said though, I'm too old now.

Valeyard posted:

hopefully YOSPOS BICTH, note the misspelling to protect the kids

Sniep posted:

Sniep posted:

prefect posted:

just what is tat, anyway?

prefect posted:

just what is tat, anyway?

Sweevo posted:

tit for tat - retribution or retaliation, an exchange insults or attacks - 'tit for tat' evolved from 'tip for tap', a middle English expression for blow for blow, which also meant a trade of verbal insults. Tit is an old English word for tug or jerk. Tat evolved from tap partly because of the alliteration with tit, but also from the verbal argument aspect, which drew on the influence of the Middle English 'tatelen' meaning prattle, (Dutch tatelen meant stammer) which also gave rise to tittle-tattle. Tip and tap are both very old words for hit. (eg 'tip and run' still describes a bat and ball game when the player hits the ball and runs, as in cricket). Tit for tat was certainly in use in the mid-late 16th century. Tip for Tap was before this. As with lots of these old expressions, their use has been strengthened by similar sounding foreign equivalents, especially from N.Europe, in this case 'dit vor dat' in Dutch, and 'tant pour tant' in French. Skeat's 1882 dictionary of etymology references 'tit for tat' in 'Bullinger's Works' . Brewer in 1870 suggests for 'tit for tat' the reference 'Heywood', which must be John Heywood, English playwright 1497-1580 (not to be confused with another English playwright Thomas Heywood 1574-1641). According to James Rogers dictionary of quotes and cliches, John Heywood used the 'tit for tat' expression in 'The Spider and the Flie' 1556.

Sweevo posted:

tit for tat - retribution or retaliation, an exchange insults or attacks - 'tit for tat' evolved from 'tip for tap', a middle English expression for blow for blow, which also meant a trade of verbal insults. Tit is an old English word for tug or jerk. Tat evolved from tap partly because of the alliteration with tit, but also from the verbal argument aspect, which drew on the influence of the Middle English 'tatelen' meaning prattle, (Dutch tatelen meant stammer) which also gave rise to tittle-tattle. Tip and tap are both very old words for hit. (eg 'tip and run' still describes a bat and ball game when the player hits the ball and runs, as in cricket). Tit for tat was certainly in use in the mid-late 16th century. Tip for Tap was before this. As with lots of these old expressions, their use has been strengthened by similar sounding foreign equivalents, especially from N.Europe, in this case 'dit vor dat' in Dutch, and 'tant pour tant' in French. Skeat's 1882 dictionary of etymology references 'tit for tat' in 'Bullinger's Works' . Brewer in 1870 suggests for 'tit for tat' the reference 'Heywood', which must be John Heywood, English playwright 1497-1580 (not to be confused with another English playwright Thomas Heywood 1574-1641). According to James Rogers dictionary of quotes and cliches, John Heywood used the 'tit for tat' expression in 'The Spider and the Flie' 1556.

PK loving SUBBAN posted:

I hacked into a nuclear facility in the '80s. You're welcome.

pro-watch

http://edition.cnn.com/2015/03/11/tech/computer-hacker-essay-414s/index.html

Sweevo posted:

tit for tat - retribution or retaliation, an exchange insults or attacks - 'tit for tat' evolved from 'tip for tap', a middle English expression for blow for blow, which also meant a trade of verbal insults. Tit is an old English word for tug or jerk. Tat evolved from tap partly because of the alliteration with tit, but also from the verbal argument aspect, which drew on the influence of the Middle English 'tatelen' meaning prattle, (Dutch tatelen meant stammer) which also gave rise to tittle-tattle. Tip and tap are both very old words for hit. (eg 'tip and run' still describes a bat and ball game when the player hits the ball and runs, as in cricket). Tit for tat was certainly in use in the mid-late 16th century. Tip for Tap was before this. As with lots of these old expressions, their use has been strengthened by similar sounding foreign equivalents, especially from N.Europe, in this case 'dit vor dat' in Dutch, and 'tant pour tant' in French. Skeat's 1882 dictionary of etymology references 'tit for tat' in 'Bullinger's Works' . Brewer in 1870 suggests for 'tit for tat' the reference 'Heywood', which must be John Heywood, English playwright 1497-1580 (not to be confused with another English playwright Thomas Heywood 1574-1641). According to James Rogers dictionary of quotes and cliches, John Heywood used the 'tit for tat' expression in 'The Spider and the Flie' 1556.

Silver Alicorn posted:

ashens calls low quality cheap goods "tat" on his youtube channel

MORE CURLY FRIES posted:

i think it comes from frayed clothes being tatty

graph posted:

tattered ?

Sweevo posted:

tit for tat - retribution or retaliation, an exchange insults or attacks - 'tit for tat' evolved from 'tip for tap', a middle English expression for blow for blow, which also meant a trade of verbal insults. Tit is an old English word for tug or jerk. Tat evolved from tap partly because of the alliteration with tit, but also from the verbal argument aspect, which drew on the influence of the Middle English 'tatelen' meaning prattle, (Dutch tatelen meant stammer) which also gave rise to tittle-tattle. Tip and tap are both very old words for hit. (eg 'tip and run' still describes a bat and ball game when the player hits the ball and runs, as in cricket). Tit for tat was certainly in use in the mid-late 16th century. Tip for Tap was before this. As with lots of these old expressions, their use has been strengthened by similar sounding foreign equivalents, especially from N.Europe, in this case 'dit vor dat' in Dutch, and 'tant pour tant' in French. Skeat's 1882 dictionary of etymology references 'tit for tat' in 'Bullinger's Works' . Brewer in 1870 suggests for 'tit for tat' the reference 'Heywood', which must be John Heywood, English playwright 1497-1580 (not to be confused with another English playwright Thomas Heywood 1574-1641). According to James Rogers dictionary of quotes and cliches, John Heywood used the 'tit for tat' expression in 'The Spider and the Flie' 1556.

Yodzilla posted:

https://www.youtube.com/watch?v=vwKTaOvhVdg

Yodzilla posted:

https://www.youtube.com/watch?v=vwKTaOvhVdg