# Granular Absorbing States (Exp)

###### tags: `experimental results` `SoftQC` `experimental setup` `granular`

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### Owners (the only one with the permission to edit the main test)

EF, AP, FS, GF

## Abs measurements

### 17/01/2025

#### Analysis of data taken the 17/07/2024

Good particle detection using two samples. One for regular grains, one for grains close to the top(?) wall on which the light spots are a bit different (fromExpToDumpLammps_OnlySmall_NoAnod.py). Still not perfect detection near the walls so I do both full system analysis and subsystem analysis.

frActive VS time for different amplitudes
(FULL SYSTEM)
(SUB SYSTEM)

frActive VS amp
(FULL SYSTEM)

(SUB SYSTEM)

### 17/07/2024

#### Small beadS $\sigma=1.2$ mm $h=3$ mm

Good driving for start and mix system $f=230$ Hz Amp=350.

Good driving Puglisi reference $f=180$ Hz Amp=190 (this is also good to start actually)

Good driving asynch bouncing up and down $f=53$ Hz Amp=190

INTERESTING OBSERVATION SAME NUMBER OF PARTICLES

$f=53$ Hz Amp=110 : quite fluid (check if synch or not)

$f=53$ Hz Amp=140 : quite absorbed (and synch, actually better check)

$f=53$ Hz Amp=190 : fluid (and asynch)

$f=53$ Hz Amp=300 : absorbed (synch? asynch?)

Guess: from 190 to 160 you go in the active phase because of synchronization

MEMO: good drivign for Brownian dynamics 164 Hz and 185 mVpp and similar

#### Test of synch asynch
I did a test to see if going from Amp=120 (Asynch) to Amp=70 (Synch) I see the effect of synchronization that stregthen the absorbtion. The proble is that at Amp=70 we are very close to detachment transition $\Gamma=1.35$ so some particle do not really bounce between the two plates and are much more free. To tio a reliable test we should find a Synch to Asynch transiotion for increasing Amp starting from much higher amplitudes where all the grains are always bouncing between the two plates.

### 13/06/2024

Start of the extensive measurement. I will explore $h=4=1.6\sigma$ mm $f=41$ Hz $A=120,190$ mVpp. 120 is Asynch in the single particle experiment while 190 is synch. Experiment as a function of $\phi$.

**Practical Info**
Exp time: 3000. Run duration: 30 seconds . Good nitial shaking: $f=95$ Hz.

frac act VS phi Full Acq

frac act VS phi around transition
frac act VS phi around transition SUBSYSTEM
StdDev (frac act) VS phi around transition

fract act VS phi amp=120 from abs state to first "very active" one

fract act VS phi amp=190 from abs state to first "very active" one

### 10-12/06/2024
Comment on what you did

### 09/10/2023 $f=53$, $h=6$ mm $=2.4\sigma$

Acquisition at two amplitudes. amp=170 was perfectly synchro with one particle, amp=140 less perfectly synch.

frac act VS phi around transition
StdDev (frac act) VS phi around transition

fract act VS phi amp=140 from abs state to first "very active" one
fract act VS phi amp=170 from abs state to first "very active" one

### 04/10/2023 $f=29$, $h=6$ mm $=2.4\sigma$
I start with the same ExpTime=5575 and fps=30 used in 2022.
BAD data, plate was not well calibrated horizontally

## Synch measurements

### 16/07/2024
Still exploration at 41 Hz $\sigma=2.5$ mm $h=4$ mm

I have found a chaos to synch transition by lowering Amp

Amp=130

Amp=110

Amp=90

Amp=70

A problem can be the fact that for amp=70 we are very close to accelerationg $\Gamma=1.135$ measured with oscillo (look logbook)

### 12/06/2024
New acquisition card Digilent
Data and script: ~/Desktop/Experiment/analisiSynchroDigilent

Each triplet of $f$, $A$ and $h$ I measure peak to peak in Oscillo and then track 70 periods with the Digilent. Used steell beads $\sigma=2.5$ mm.

**Amplitude table**
| $A$ (gen) $\downarrow$ --- $f$ $\rightarrow$ | 29 | 41 | 53 |
| ------------------------------------------- | ---- | ----- | ---- |
| 120 mVpp = |392 mVpp (osc) = | 360 mVpp (osc) = | 344 mVpp (osc) =
| 155 mVpp = |512 mVpp (osc) = | 464 mVpp (osc) = | 463 mVpp (osc) =
| 190 mVpp = |612 mVpp (osc) = | 552 mVpp (osc) = | 516 mVpp (osc) =

$h=6$ mm (2.4$\sigma$)
**Synch table**

| $A$ (gen) $\downarrow$ --- $f$ $\rightarrow$ | 29 | 41 | 53 |
| ------------------------------------------- | ---- | ----- | ---- |
| 120 mVpp | As | Sy | Sy
| 155 mVpp | As? | Sy | Sy
| 190 mVpp | As? | Sy | Sy

Example ASynch
$f$=29 hZ A=120 mVpp

Example Synch
$f$=53 hZ A=120 mVpp

$h=4$ mm (1.6$\sigma$)

**Synch table**
| $A$ (gen) $\downarrow$ --- $f$ $\rightarrow$ | 29 | 41 | 53 |
| ------------------------------------------- | ---- | ----- | ---- |
| 120 mVpp | As | As | Sy
| 155 mVpp | Sy | Sy | Sy
| 190 mVpp | Sy | Sy | Sy

Example Synch One Particle
$f$=41 hZ A=190 mVpp

Example Asynch One particle
$f$=41 hZ A=120 mVpp

Example Synch 327 Particles
$f$=41 hZ A=190 mVpp

Example Asynch 327 particles
$f$=41 hZ A=120 mVpp

### 03/10/2023
Fracois verified that with our oscilloscope we cannot do a signal acquisition of the desired length with the same acquisition rate. The oscilloscope only acquirers 2500 points. We are ordering an acquisition card to do precise synch VS asynch measurements of the desired duration.

While waiting for that I looked for a condition in which synch and asynch motion can be clearly distinguished by eyes looking only few periods. I changed the height of the cell thanks to the spacers homemade by Francois 1 year ago. In this way I reached h=1.4*sigma (second row from the bottom of our map in fig 4c). Here I can basically recover the behaviour predicted by simulations in this condition.

h=1.4sigma A=0.04sigma:
Lammps predicts Asynch, Exp shows collisions in different positions each period


h=1.4sigma A=0.1sigma
Lammps predicts Synch, Exp shows collisions in the same positions each period


I show plots in which I superimposes 5 consecutive periods acquired with the oscilloscope.

The problem of this condition is that the homemade spacers are not so reliable. We could have the glass plate slightly
inclined. I want to do again this test for h=3 mm= 1.2*sigma using only the support made in the workshop.

h=1.2sigma A=?sigma:
Lammps predicts Asynch, Exp shows collisions in different positions each period

h=1.2sigma A=?sigma
Lammps predicts Synch, Exp shows collisions in the same positions each period

h=3 mm also works for synch VS asynch but it is not good since particles basically don't move balistically. Probably for this height the abs-active transition is above crystallization point which is not the case we want to explore.

Anyway, I found another spot for h=6mm = 2.4sigma where I have Synch and asynch only varying amplitude

h=2.4sigma A=0.26sigma:
Lammps predicts Asynch, Exp shows collisions in different positions each period

h=2.4sigma A=0.29sigma
Lammps predicts Synch, Exp shows collisions in the same positions each period

## Calibration
(05/10/23)
I found a good condition for calibration:
**h=6 mm f=120 Hz A= 160 mVpp glass plate L=0.2 m ExpTime=5575 N=514 ($\phi=0.063$)**.


Not perf homogeneous but much better than yesterday. I'll continue with this

(04/10/23)
Script modified for L=0.2 m. There is a problem of inhomogeneous motion for driving parameters that are good for calib.

## Explorative Study 2022
### GIF
$\phi < \phi_c$

$\phi \sim \phi_c$

$\phi > \phi_c$

### Fraction of active particles

#### $f=53$ Hz $A_o=170$ $mV_{pp}$ **varying phi**
This analisys can be surely refined but it seems to work. I'll add some details later.

There are some artifact that I will explain. But they don't affrct the final results.

#### $f=53$ Hz $\phi=0.12$ **varying $A_o$**